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  • richardmitnick 5:06 pm on February 4, 2023 Permalink | Reply
    Tags: "The Origin of the Origin of the Universe", , , , , , , , , , ,   

    From Astrobites : “The Origin of the Origin of the Universe” 

    Astrobites bloc

    From Astrobites

    2.4.23
    Katherine Lee

    Title: Measurement of the Cosmic Microwave Background Spectrum by the COBE FIRAS Instrument

    Authors: J. C. Mather, E. S. Cheng, D. A. Cottingham, R. E. Eplee Jr., D. J. Fixsen, T. Hewagama, R. B. Isaacman, K. A. Jensen, S. S. Meyer, P. D. Noerdlinger, S. M. Read, L. P. Rosen, R. A. Shafer, E. L. Wright, C. L. Bennett, N. W. Boggess, M. G. Hauser, T. Kelsall, S. H. Moseley Jr., R. F. Silverberg, G. F. Smoot, R. Weiss, and D. T. Wilkinson

    First Author’s Institution: NASA Goddard Space Flight Center, Greenbelt, Maryland, USA

    Status: published in ApJ [open access]

    Back in the mid-20th century, there were two competing theories about the origin of the Universe. Scientists, including Edwin Hubble and Georges Lemaître, had already established that space was expanding.

    ______________________________________________________________________________
    Edwin Hubble

    .


    ______________________________________________________________________________

    Some argued that if you run this expansion back in time, it implies a beginning when everything must have been compressed into a hot, dense singularity, exploding outward from that point in a “Big Bang”. Other astronomers, however, were uncomfortable with the idea that the Universe even had an origin at all. These scientists, most notably Fred Hoyle, argued instead for a cosmology in which the Universe had always existed and had always been expanding, with new galaxies springing up periodically to fill in the gaps. This picture of our Universe is referred to as the “Steady State Theory”.

    These two theories predict fundamentally different things about the background temperature of the Universe. If matter in the Universe does not originate from a single point, as in the Steady State picture, then we would expect the background radiation to be chaotic in nature; there would be no reason for different unconnected regions of spacetime to look the same as each other.

    However, if everything in the Universe comes from the same initial conditions, then everything should be roughly the same temperature. This can also be expressed as the idea that the Universe should be in thermodynamic equilibrium on large scales, and that if you measure the intensity of background radiation at all frequencies, you should see a blackbody spectrum—the characteristic spectrum of an object in equilibrium, dependent only on the object’s temperature. Thus, a key prediction of the Big Bang theory is that the temperature should be nearly constant over the entire sky, with the differences (called anisotropies) from this constant average temperature being extremely small—around one part in 100,000!

    COBE comes to the rescue

    Big Bang cosmologists in the 1960s believed that the peak of the Universe’s blackbody spectrum should be in the microwave frequency range, defined as between 300 MHz and 300 GHz. This would be expected from a massive explosion of energy at the Big Bang, the light from which would have been redshifted into the microwave range as it traveled through the expanding universe. So, if the Big Bang theory is true, we should expect to see a constant source of background radiation coming from all directions in the microwave sky: a so-called Cosmic Microwave Background, or CMB.

    The detection of this CMB radiation in 1965 by Arno Penzias and Robert Woodrow Wilson, as well as the cosmological interpretation of that detection by Robert Dicke, Jim Peebles, Peter Roll, and David Wilkinson, laid the groundwork for modern cosmology, and was the beginning of the end for the idea that the Universe had no origin.

    However, Penzias and Wilson’s discovery was not an accurate measurement of the CMB’s temperature or spectrum. No anisotropies had been detected, and there was still debate over whether or not the CMB spectrum was truly a blackbody. The goal of the Cosmic Background Explorer (COBE) satellite, launched by NASA in 1989, was to answer these lingering questions.

    COBE was split into three instruments: the Differential Microwave Radiometer (DMR), the Far-InfraRed Absolute Spectrophotometer (FIRAS), and the Diffuse Infrared Background Experiment (DIRBE). DMR measured the CMB anisotropies, while DIRBE mapped infrared radiation from foreground dust.

    2
    igure 1: A diagram of the FIRAS instrument, taken from Figure 1a of Mather et. al. (1999).

    FIRAS, meanwhile, was designed to measure the CMB spectrum. It scanned the entire sky multiple times in order to minimize errors, and measured the temperature over a wide range of frequencies between 30 and FIRAS, meanwhile, was designed to measure the CMB spectrum. It scanned the entire sky multiple times in order to minimize errors and measured the temperature over a wide range of frequencies between 30 and nearly 3000 GHz. After eliminating known sources of interference such as cosmic rays, as well as subtracting the effects of light from the Milky Way galaxy and of the Doppler shift caused by the movement of the Earth through space, these scans were then averaged together to create direct measurements of the CMB intensity at various frequencies.

    2
    Figure 2: The cosmic microwave background spectrum, as measured by FIRAS. It shows a near-perfect blackbody, with any deviations from total thermodynamic equilibrium being much too small to see. This plot is taken from Figure 4 of Fixsen et al. (1996), which notes that “uncertainties are a small fraction of the line thickness.”line thickness.”

    The authors found that the background radiation in our universe is in fact extremely close to being a perfect bThe authors of today’s paper found that the background radiation in our Universe is in fact extremely close to being a perfect blackbody! The final temperature found by FIRAS was reported by Mather et al. (1999) to be 2.725 K, with an uncertainty of just 0.002 K! This is an incredibly high-precision measurement and represents the final nail in the coffin for cosmologies other than the Big Bang. John C. Mather received the Nobel Prize in 2006 for his work as FIRAS’s project lead.

    3
    Figure 3: A comparison of the abilities of the COBE [above], WMAP, and Planck satellites to resolve tiny fluctuations in the CMB temperature, called anisotropies. Image: NASA/JPL-Caltech/ESA (Wikimedia Commons)




    Today, cosmologists use the CMB and its anisotropies to characterize the early history of the universe, find galaxy clusters in the later universe, and even look for new physics! The COBE measurements represented the dawn of a new era in cosmology, and laid the groundwork for modern CMB measurements. The science we do toToday, cosmologists use the CMB and its anisotropies to characterize the early history of the Universe, find galaxy clusters in the later Universe, and even look for new physics! Later full-sky measurements taken by the Wilkinson Microwave Anisotropy Probe (WMAP) and the Planck satellite added never-before-seen levels of precision to our ability to study the structure and content of the Universe, and future missions like LiteBIRD will continue to improve our ability to study the CMB even more closely, building on COBE’s groundbreaking data. These experiments still rely upon the CMB temperature established by FIRAS, which remains the definitive result even 23 years after its publication.

    ___________________________________________________________________
    Inflation

    In physical cosmology, cosmic inflation, cosmological inflation is a theory of exponential expansion of space in the early universe. The inflationary epoch lasted from 10^−36 seconds after the conjectured Big Bang singularity to some time between 10^−33 and 10^−32 seconds after the singularity. Following the inflationary period, the universe continued to expand, but at a slower rate. The acceleration of this expansion due to dark energy began after the universe was already over 7.7 billion years old (5.4 billion years ago).

    Inflation theory was developed in the late 1970s and early 80s, with notable contributions by several theoretical physicists, including Alexei Starobinsky at Landau Institute for Theoretical Physics, Alan Guth at Cornell University, and Andrei Linde at Lebedev Physical Institute. Alexei Starobinsky, Alan Guth, and Andrei Linde won the 2014 Kavli Prize “for pioneering the theory of cosmic inflation.” It was developed further in the early 1980s. It explains the origin of the large-scale structure of the cosmos. Quantum fluctuations in the microscopic inflationary region, magnified to cosmic size, become the seeds for the growth of structure in the Universe. Many physicists also believe that inflation explains why the universe appears to be the same in all directions (isotropic), why the cosmic microwave background radiation is distributed evenly, why the universe is flat, and why no magnetic monopoles have been observed.

    The detailed particle physics mechanism responsible for inflation is unknown. The basic inflationary paradigm is accepted by most physicists, as a number of inflation model predictions have been confirmed by observation; however, a substantial minority of scientists dissent from this position. The hypothetical field thought to be responsible for inflation is called the inflaton.

    In 2002 three of the original architects of the theory were recognized for their major contributions; physicists Alan Guth of M.I.T., Andrei Linde of Stanford, and Paul Steinhardt of Princeton shared the prestigious Dirac Prize “for development of the concept of inflation in cosmology”. In 2012 Guth and Linde were awarded the Breakthrough Prize in Fundamental Physics for their invention and development of inflationary cosmology.

    4
    Alan Guth, from M.I.T., who first proposed Cosmic Inflation.

    Alan Guth’s notes:
    Alan Guth’s original notes on inflation.
    ___________________________________________________________________

    Nobel Prize in Physics for 2011 Expansion of the Universe

    4 October 2011

    The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2011

    with one half to

    Saul Perlmutter
    The Supernova Cosmology Project
    The DOE’s Lawrence Berkeley National Laboratory and The University of California-Berkeley,

    and the other half jointly to

    Brian P. SchmidtThe High-z Supernova Search Team, The Australian National University, Weston Creek, Australia.

    and

    Adam G. Riess

    The High-z Supernova Search Team,The Johns Hopkins University and The Space Telescope Science Institute, Baltimore, MD.

    Written in the stars

    “Some say the world will end in fire, some say in ice…” *

    What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.

    In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.

    The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.

    The teams used a particular kind of supernova, called Type 1a supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.

    For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.

    The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.

    *Robert Frost, Fire and Ice, 1920
    ______________________________________________________________________________

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    What do we do?

    Astrobites is a daily astrophysical literature journal written by graduate students in astronomy. Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.
    Why read Astrobites?

    Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.

    Our goal is to solve this problem, one paper at a time. In 5 minutes a day reading Astrobites, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in a new area of astronomy.

     
  • richardmitnick 2:52 pm on February 4, 2023 Permalink | Reply
    Tags: "A world with no weak forces", , , , ,   

    From particlebites: “A world with no weak forces” 

    particlebites bloc

    From particlebites

    2.4.23
    Nirmal Raj

    Gravity, electromagnetism, strong, and weak — these are the beating hearts of the universe, the four fundamental forces. But do we really need the last one for us to exist?

    Harnik, Kribs and Perez went about building a world without weak interactions and showed that, indeed, life as we know it could emerge there. This was a counter-proof by example to a famous anthropic argument by Agrawal, Barr, Donoghue and Seckel for the puzzling tininess of the weak scale, i.e. the electroweak hierarchy problem.

    1
    Summary of the argument in hep-ph/9707380 that a tiny Higgs mass (in Planck mass units) is necessary for life to develop.

    Let’s ask first: would the Sun be there in a weakless universe? Sunshine is the product of proton fusion, and that’s the strong force. However, the reaction chain is ignited by the weak force!

    2
    image: Eric G. Blackman.

    So would no stars shine in a weakless world? Amazingly, there’s another route to trigger stellar burning: deuteron-proton fusion via the strong force! In our world, gas clouds collapsing into stars do not take this option because deuterons are very rare, with protons outnumbering them by 50,000. But we need not carry this, er, weakness into our gedanken universe. We can tune the baryon-to-photon ratio — whose origin is unknown — so that we end up with roughly as many deuterons as protons from the primordial synthesis of nuclei. Harnik et al. go on to show that, as in our universe, elements up to iron can be cooked in weakless stars, that they live for billions of years, and may explode in supernovae that disperse heavy elements into the interstellar medium.

    3
    source: hep-ph/0604027

    A “weakless” universe is arranged by elevating the electroweak scale or the Higgs vacuum expectation value (\approx 246 GeV) to, say, the Planck scale (\approx 10^{19} GeV). To get the desired nucleosynthesis, care must be taken to keep the u, d, s quarks and the electron at their usual mass by tuning the Yukawa couplings, which are technically natural.

    And let’s not forget dark matter. To make stars, one needs galaxy-like structures. And to make those, density perturbations must be gravitationally condensed by a large population of matter. In the weakless world of Harnik et al., hyperons make up some of the dark matter, but you would also need much other dark stuff such as your favourite non-WIMP.

    If you believe in the string landscape, a weakless world isn’t just a hypothetical. Someone somewhere might be speculating about a habitable universe with a fourth fundamental force, explaining to their bemused colleagues: “It’s kinda like the strong force, only weak…”

    4

    Bibliography

    Viable range of the mass scale of the standard model
    V. Agrawal, S. M. Barr, J. F. Donoghue, D. Seckel, Phys.Rev.D 57 (1998) 5480-5492.

    A Universe without weak interactions
    R. Harnik, G. D. Kribs, G. Perez, Phys.Rev.D 74 (2006) 035006

    Further reading

    Gedanken Worlds without Higgs: QCD-Induced Electroweak Symmetry Breaking
    C. Quigg, R. Shrock, Phys.Rev.D 79 (2009) 096002

    The Multiverse and Particle Physics
    J. F. Donoghue, Ann.Rev.Nucl.Part.Sci. 66 (2016)

    The eighteen arbitrary parameters of the standard model in your everyday life
    R. N. Cahn, Rev. Mod. Phys. 68, 951 (1996)

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    What is ParticleBites?
    ParticleBites is an online particle physics journal club written by graduate students and postdocs. Each post presents an interesting paper in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.

    The papers are accessible on the arXiv preprint server. Most of our posts are based on papers from hep-ph (high energy phenomenology) and hep-ex (high energy experiment).

    Why read ParticleBites?

    Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.

    Our goal is to solve this problem, one paper at a time. With each brief ParticleBite, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in particle physics.

    Who writes ParticleBites?

    ParticleBites is written and edited by graduate students and postdocs working in high energy physics. Feel free to contact us if you’re interested in applying to write for ParticleBites.

    ParticleBites was founded in 2013 by Flip Tanedo following the Communicating Science (ComSciCon) 2013 workshop.

    2
    Flip Tanedo UCI Chancellor’s ADVANCE postdoctoral scholar in theoretical physics. As of July 2016, I will be an assistant professor of physics at the University of California, Riverside

    It is now organized and directed by Flip and Julia Gonski, with ongoing guidance from Nathan Sanders.

     
  • richardmitnick 2:21 pm on February 4, 2023 Permalink | Reply
    Tags: "Serendipitous detection of a rapidly accreting black hole in the early Universe", , , , , , eRosita Russian German space X-ray telescope, The MPG Institute for Extraterrestrial Physics [MPG Institut für Extraterrestrische Physik](DE)   

    From The MPG Institute for Extraterrestrial Physics [MPG Institut für Extraterrestrische Physik](DE): “Serendipitous detection of a rapidly accreting black hole in the early Universe” 

    From The MPG Institute for Extraterrestrial Physics [MPG Institut für Extraterrestrische Physik](DE)

    1.31.23

    Wolf, Julien
    phd student
    Tel +49 89 30000-3879
    Fax +49 89 30000-3569
    jwolf@mpe.mpg.de

    Salvato, Mara
    Senior Scientist
    Tel +49 89 30000-3815
    Fax +49 89 30000-3569
    mara@mpe.mpg.de

    Nandra, Kirpal
    director
    Tel +49 89 30000-3401
    Fax +49 89 30000-3569
    knandra@mpe.mpg.de

    eROSITA telescope finds an X-ray bright, optically faint quasar accreting material at an extremely high rate only about 800 million years after the big bang.

    Analyzing data from the eROSITA Final Equatorial-Depth Survey, astronomers at MPE have found a faint X-ray source identified with a very distant supermassive black hole that is accreting material at an extremely high rate. This quasar, at a redshift of z=6.56, is much more luminous in X-rays than expected. This is the most distant blind X-ray detection to date, from an object whose radiation was emitted almost 13 billion years ago and allows the scientists to investigate the growth of black holes in the early Universe.

    Supermassive black holes at the centres of galaxies can be detected out to great distances – but only if they accrete matter, which heats up and shines brightly, causing it to become an “active galactic nucleus” (AGN). These “quasars” or quasi-stellar objects then outshine the rest of their galaxy, but at large distances, they nevertheless are difficult to detect and extremely rare. To date, only about 50 quasars with redshift z>5.7, when the Universe was less than one billion years old, have been detected in X-rays.

    2
    A new, faint X-ray source (right) was found in the eROSITA Final Equatorial-Depth Survey (eFEDS). Using optical follow-up observations (left top), the eROSITA team identified this as a quasar at a redshift of z=6.56. Quasars are powered by a central supermassive black hole, accreting material at a high rate. This is the most distant blind X-ray detection to date and allows the scientists to investigate the growth of black holes in the early Universe. Collage: MPE/Cluster Origins.

    Analyzing X-ray data of the eROSITA Final Equatorial-Depth Survey (eFEDS), which were taken during the Performance Verification Phase of the eROSITA telescope in 2019, the eROSITA team found a new point source. In collaboration with colleagues using the Subaru telescope, they identified the X-ray emission with a previously known quasar J0921+0007 at a redshift of 6.56, which was initially discovered by a team searching for distant sources with the Subaru telescope.


    Dedicated follow-up observations at infrared wavelengths showed that the black hole has 250 million solar masses, a relatively low mass for a supermassive black hole at this distance. Chandra follow-up observations confirmed the high X-ray luminosity measured by eROSITA, indicating a very high accretion rate.

    “We did not expect to find such a low-mass AGN already in our very first mini-survey with eROSITA”, says Julien Wolf, who searches for the most distant supermassive black holes in eROSITA data as part of his Ph.D. at the Max Planck Institute for Extraterrestrial Physics (MPE). “It is the most distant serendipitous X-ray detection to date and its properties are rather atypical for quasars at such high redshifts: it is intrinsically faint in visible light but very luminous in X-rays.”

    The quasar detected by eROSITA shows properties, which are similar to so-called narrow-line Seyfert-1 galaxies, a particular class of active galaxies in the local Universe. They are associated with supermassive black holes below 100 million solar masses, accreting matter at a high rate, and could be younger than their higher mass siblings.

    “Hunting for rare objects like this needs deep multi-wavelength data complementing the large X-ray survey area. Luckily, most of the sky is mapped at optical and infrared wavelengths, although the Subaru data in eFEDS area are especially deep,” emphasises Mara Salvato, eROSITA spokesperson.

    3
    X-ray image cutouts in the region of J0921+0007. The eROSITA/eFEDS image is on the left, the high-resolution Chandra image is on the right. © MPE

    While the bulk of active galaxies detected at high redshifts (i.e. large distances) host black holes with masses of one to ten billion solar masses, there must also be many with less massive black holes. These, however, need to accrete matter at a very high rate to shine brightly enough so that they can be detected at all.

    In addition to this source, the team had earlier found another luminous and similarly distant quasar in the same field. “eROSITA is uniquely suited to performing a census of rare X-ray objects like these powerful high-redshift quasars,” states Kirpal Nandra, director of high-energy physics at MPE. “This is now the second example we’ve found in eFEDS when we expected to find none”.

    The early eROSITA data are just a foretaste of what’s to come. Based on these early detections, the scientists expect to find hundreds more examples with the eROSITA all-sky survey. In an effort to find this elusive population of yet unknown distant quasars, the group has developed a large programme exploring the eROSITA all-sky survey. This dedicated survey has already led to the discovery of five new X-ray luminous quasars at z>5.6, which will be presented in a future publication. Simultaneously, a Russian team of researchers have also reported the first eROSITA high-redshift detections in the northern hemisphere.

    Objects like these are currently our best way of understanding early black hole formation. If the surprising eFEDS detections are confirmed in the larger dataset, it could represent a challenge for some evolutionary models.

    Astronomy & Astrophysics

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    For their astrophysical research, The MPG Institute for Extraterrestrial Physics [MPG Institut für Extraterrestrische Physik]( DE) scientists measure the radiation of far away objects in different wavelenths areas: from millimetere/sub-millimetre and infared all the way to X-ray and gamma-ray wavelengths. These methods span more than twelve decades of the electromagnetic spectrum.

    The research topics pursued at MPE range from the physics of cosmic plasmas and of stars to the physics and chemistry of interstellar matter, from star formation and nucleosynthesis to extragalactic astrophysics and cosmology. The interaction with observers and experimentalists in the institute not only leads to better consolidated efforts but also helps to identify new, promising research areas early on.

    The structural development of the institute mainly has been directed by the desire to work on cutting-edge experimental, astrophysical topics using instruments developed in-house. This includes individual detectors, spectrometers and cameras but also telescopes and integrated, complete payloads. Therefore the engineering and workshop areas are especially important for the close interlink between scientific and technical aspects.

    The scientific work is done in four major research areas that are supervised by one of the directors:

    Center for Astrochemical Studies (CAS)
    High-Energy Astrophysics
    Infrared/Submillimeter Astronomy
    Optical & Interpretative Astronomy

    Within these areas scientists lead individual experiments and research projects organized in about 25 project teams.

    MPG Society for the Advancement of Science [MPG Gesellschaft zur Förderung der Wissenschaften e. V.] (DE)is a formally independent non-governmental and non-profit association of German research institutes founded in 1911 as the Kaiser Wilhelm Society and renamed the Max Planck Society in 1948 in honor of its former president, theoretical physicist Max Planck. The society is funded by the federal and state governments of Germany as well as other sources.

    According to its primary goal, the MPG Society supports fundamental research in the natural, life and social sciences, the arts and humanities in its 83 (as of January 2014) MPG Institutes. The society has a total staff of approximately 17,000 permanent employees, including 5,470 scientists, plus around 4,600 non-tenured scientists and guests. Society budget for 2015 was about €1.7 billion.

    The MPG Institutes focus on excellence in research. The MPG Society has a world-leading reputation as a science and technology research organization, with 33 Nobel Prizes awarded to their scientists, and is generally regarded as the foremost basic research organization in Europe and the world. In 2013, the Nature Publishing Index placed the MPG institutes fifth worldwide in terms of research published in Nature journals (after Harvard University, The Massachusetts Institute of Technology, Stanford University and The National Institutes of Health). In terms of total research volume (unweighted by citations or impact), the Max Planck Society is only outranked by The Chinese Academy of Sciences [中国科学院](CN), The Russian Academy of Sciences [Росси́йская акаде́мия нау́к](RU) and Harvard University. The Thomson Reuters-Science Watch website placed the MPG Society as the second leading research organization worldwide following Harvard University, in terms of the impact of the produced research over science fields.

    The MPG Society and its predecessor Kaiser Wilhelm Society hosted several renowned scientists in their fields, including Otto Hahn, Werner Heisenberg, and Albert Einstein.

    History

    The organization was established in 1911 as the Kaiser Wilhelm Society, or Kaiser-Wilhelm-Gesellschaft (KWG), a non-governmental research organization named for the then German emperor. The KWG was one of the world’s leading research organizations; its board of directors included scientists like Walther Bothe, Peter Debye, Albert Einstein, and Fritz Haber. In 1946, Otto Hahn assumed the position of President of KWG, and in 1948, the society was renamed the Max Planck Society (MPG) after its former President (1930–37) Max Planck, who died in 1947.

    The MPG Society has a world-leading reputation as a science and technology research organization. In 2006, the Times Higher Education Supplement rankings of non-university research institutions (based on international peer review by academics) placed the MPG Society as No.1 in the world for science research, and No.3 in technology research (behind AT&T Corporation and The DOE’s Argonne National Laboratory.

    The domain mpg.de attracted at least 1.7 million visitors annually by 2008 according to a Compete.com study.

    MPG Institutes and research groups

    The MPG Society consists of over 80 research institutes. In addition, the society funds a number of Max Planck Research Groups (MPRG) and International Max Planck Research Schools (IMPRS). The purpose of establishing independent research groups at various universities is to strengthen the required networking between universities and institutes of the Max Planck Society.
    The research units are primarily located across Europe with a few in South Korea and the U.S. In 2007, the Society established its first non-European centre, with an institute on the Jupiter campus of Florida Atlantic University (US) focusing on neuroscience.
    The MPG Institutes operate independently from, though in close cooperation with, the universities, and focus on innovative research which does not fit into the university structure due to their interdisciplinary or transdisciplinary nature or which require resources that cannot be met by the state universities.

    Internally, MPG Institutes are organized into research departments headed by directors such that each MPI has several directors, a position roughly comparable to anything from full professor to department head at a university. Other core members include Junior and Senior Research Fellows.

    In addition, there are several associated institutes:

    International Max Planck Research Schools

    International Max Planck Research Schools

    Together with the Association of Universities and other Education Institutions in Germany, the Max Planck Society established numerous International Max Planck Research Schools (IMPRS) to promote junior scientists:

    • Cologne Graduate School of Ageing Research, Cologne
    • International Max Planck Research School for Intelligent Systems, at the Max Planck Institute for Intelligent Systems located in Tübingen and Stuttgart
    • International Max Planck Research School on Adapting Behavior in a Fundamentally Uncertain World (Uncertainty School), at the Max Planck Institutes for Economics, for Human Development, and/or Research on Collective Goods
    • International Max Planck Research School for Analysis, Design and Optimization in Chemical and Biochemical Process Engineering, Magdeburg
    • International Max Planck Research School for Astronomy and Cosmic Physics, Heidelberg at the MPI for Astronomy
    • International Max Planck Research School for Astrophysics, Garching at the MPI for Astrophysics
    • International Max Planck Research School for Complex Surfaces in Material Sciences, Berlin
    • International Max Planck Research School for Computer Science, Saarbrücken
    • International Max Planck Research School for Earth System Modeling, Hamburg
    • International Max Planck Research School for Elementary Particle Physics, Munich, at the MPI for Physics
    • International Max Planck Research School for Environmental, Cellular and Molecular Microbiology, Marburg at the Max Planck Institute for Terrestrial Microbiology
    • International Max Planck Research School for Evolutionary Biology, Plön at the Max Planck Institute for Evolutionary Biology
    • International Max Planck Research School “From Molecules to Organisms”, Tübingen at the Max Planck Institute for Developmental Biology
    • International Max Planck Research School for Global Biogeochemical Cycles, Jena at the Max Planck Institute for Biogeochemistry
    • International Max Planck Research School on Gravitational Wave Astronomy, Hannover and Potsdam MPI for Gravitational Physics
    • International Max Planck Research School for Heart and Lung Research, Bad Nauheim at the Max Planck Institute for Heart and Lung Research
    • International Max Planck Research School for Infectious Diseases and Immunity, Berlin at the Max Planck Institute for Infection Biology
    • International Max Planck Research School for Language Sciences, Nijmegen
    • International Max Planck Research School for Neurosciences, Göttingen
    • International Max Planck Research School for Cognitive and Systems Neuroscience, Tübingen
    • International Max Planck Research School for Marine Microbiology (MarMic), joint program of the Max Planck Institute for Marine Microbiology in Bremen, the University of Bremen, the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, and the Jacobs University Bremen
    • International Max Planck Research School for Maritime Affairs, Hamburg
    • International Max Planck Research School for Molecular and Cellular Biology, Freiburg
    • International Max Planck Research School for Molecular and Cellular Life Sciences, Munich
    • International Max Planck Research School for Molecular Biology, Göttingen
    • International Max Planck Research School for Molecular Cell Biology and Bioengineering, Dresden
    • International Max Planck Research School Molecular Biomedicine, program combined with the ‘Graduate Programm Cell Dynamics And Disease’ at the University of Münster and the Max Planck Institute for Molecular Biomedicine
    • International Max Planck Research School on Multiscale Bio-Systems, Potsdam
    • International Max Planck Research School for Organismal Biology, at the University of Konstanz and the Max Planck Institute for Ornithology
    • International Max Planck Research School on Reactive Structure Analysis for Chemical Reactions (IMPRS RECHARGE), Mülheim an der Ruhr, at the Max Planck Institute for Chemical Energy Conversion
    • International Max Planck Research School for Science and Technology of Nano-Systems, Halle at Max Planck Institute of Microstructure Physics
    • International Max Planck Research School for Solar System Science at the University of Göttingen hosted by MPI for Solar System Research
    • International Max Planck Research School for Astronomy and Astrophysics, Bonn, at the MPI for Radio Astronomy (formerly the International Max Planck Research School for Radio and Infrared Astronomy)
    • International Max Planck Research School for the Social and Political Constitution of the Economy, Cologne
    • International Max Planck Research School for Surface and Interface Engineering in Advanced Materials, Düsseldorf at Max Planck Institute for Iron Research GmbH
    • International Max Planck Research School for Ultrafast Imaging and Structural Dynamics, Hamburg

    Max Planck Schools

    • Max Planck School of Cognition
    • Max Planck School Matter to Life
    • Max Planck School of Photonics

    Max Planck Center

    • The Max Planck Centre for Attosecond Science (MPC-AS), POSTECH Pohang
    • The Max Planck POSTECH Center for Complex Phase Materials, POSTECH Pohang

    Max Planck Institutes

    Among others:
    • Max Planck Institute for Neurobiology of Behavior – caesar, Bonn
    • Max Planck Institute for Aeronomics in Katlenburg-Lindau was renamed to Max Planck Institute for Solar System Research in 2004;
    • Max Planck Institute for Biology in Tübingen was closed in 2005;
    • Max Planck Institute for Cell Biology in Ladenburg b. Heidelberg was closed in 2003;
    • Max Planck Institute for Economics in Jena was renamed to the Max Planck Institute for the Science of Human History in 2014;
    • Max Planck Institute for Ionospheric Research in Katlenburg-Lindau was renamed to Max Planck Institute for Aeronomics in 1958;
    • Max Planck Institute for Metals Research, Stuttgart
    • Max Planck Institute of Oceanic Biology in Wilhelmshaven was renamed to Max Planck Institute of Cell Biology in 1968 and moved to Ladenburg 1977;
    • Max Planck Institute for Psychological Research in Munich merged into the Max Planck Institute for Human Cognitive and Brain Sciences in 2004;
    • Max Planck Institute for Protein and Leather Research in Regensburg moved to Munich 1957 and was united with the Max Planck Institute for Biochemistry in 1977;
    • Max Planck Institute for Virus Research in Tübingen was renamed as Max Planck Institute for Developmental Biology in 1985;
    • Max Planck Institute for the Study of the Scientific-Technical World in Starnberg (from 1970 until 1981 (closed)) directed by Carl Friedrich von Weizsäcker and Jürgen Habermas.
    • Max Planck Institute for Behavioral Physiology
    • Max Planck Institute of Experimental Endocrinology
    • Max Planck Institute for Foreign and International Social Law
    • Max Planck Institute for Physics and Astrophysics
    • Max Planck Research Unit for Enzymology of Protein Folding
    • Max Planck Institute for Biology of Ageing

     
  • richardmitnick 12:56 pm on February 4, 2023 Permalink | Reply
    Tags: "3 new studies indicate a conflict at the heart of cosmology", "The Big Think", , , , , , ,   

    From “The Big Think” : “3 new studies indicate a conflict at the heart of cosmology” 

    From “The Big Think”

    2.1.23
    Don Lincoln

    The Universe isn’t as “clumpy” as we think it should be.

    1
    Credit: NASA.

    Key Takeaways

    Telescopes are essentially time machines. As we examine galaxies that are at greater and greater distances from the Earth, we are looking further and further back in time. A new series of studies that examine the “clumpiness” of the Universe indicates that there might be a conflict at the heart of cosmology. The Big Bang theory is still sound, but it may need to be tweaked.

    A series of three scientific papers describing the expansion history of the Universe is telling a confusing tale, with predictions and measurements slightly disagreeing.

    While this disagreement isn’t considered a fatal disproof of modern cosmology, it could be a hint that our theories need to be revised.

    PRD “Joint analysis of DES Year 3 data and CMB lensing from SPT and Planck I: Construction of CMB Lensing Maps and Modeling Choices”
    PRD “Joint analysis of DES Year 3 data and CMB lensing from SPT and Planck II: Cross-correlation measurements and cosmological constraints”
    PRD “Joint analysis of DES Year 3 data and CMB lensing from SPT and Planck III: Combined cosmological constraints”

    Creation stories, both ancient and modern

    Understanding exactly how the world around us came into existence is a question that has bothered humanity for millennia. All around the world, people have devised stories — from the ancient Greek legend of the creation of the Earth and other primordial entities from Chaos (as first written down by Hesiod) to the Hopi creation myth (which describes a series of different kinds of creatures being created, eventually ending up as humans).

    In modern times, there are still competing creation stories, but there is one that is grounded in empiricism and the scientific method: the idea that about 13.8 billion years ago, the Universe began in a much smaller and hotter compressed state, and it has been expanding ever since then. This idea is colloquially called the “Big Bang,” although different writers use the term to mean slightly different things. Some use it to refer to the exact moment at which the Universe came into existence and began to expand, while others use it to refer to all moments after the beginning. For those writers, the Big Bang is still ongoing, as the expansion of the Universe continues.

    The beauty of this scientific explanation is that it can be tested. Astronomers rely on the fact that light has a finite speed, which means that it takes time for light to cross the cosmos. For example, the light we see as the Sun shining was emitted eight minutes before we see it. Light from the nearest star took about four years to get to Earth, and light from elsewhere in the cosmos can take billions of years to arrive.

    The telescope as a time machine

    Effectively, this means that telescopes are time machines. By looking at more and more distant galaxies, astronomers are able to see what the Universe looked like in the distant past. By stitching together observations of galaxies at different distances from the Earth, astronomers can unravel the evolution of the cosmos.

    The recent measurements use two different telescopes to study the structure of the Universe at different cosmic epochs. One facility, called the South Pole Telescope (SPT), looks at the earliest possible light, emitted a mere 380,000 years after the Universe began.

    At that time, the Universe was 0.003% its current age. If we consider the current cosmos to be equivalent to a 50-year-old person, the SPT looks at the Universe when it was a mere 12 hours old.

    The second facility is called the Dark Energy Survey (DES).
    ___________________________________________________________________
    The Dark Energy Survey

    Dark Energy Camera [DECam] built at The DOE’s Fermi National Accelerator Laboratory.

    NOIRLab National Optical Astronomy Observatory Cerro Tololo Inter-American Observatory (CL) Victor M Blanco 4m Telescope which houses the Dark-Energy-Camera – DECam at Cerro Tololo, Chile at an altitude of 7200 feet.

    NOIRLabNSF NOIRLab NOAO Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

    The Dark Energy Survey is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. The Dark Energy Survey began searching the Southern skies on August 31, 2013.

    According to Albert Einstein’s Theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up.

    Nobel Prize in Physics for 2011 Expansion of the Universe

    4 October 2011

    The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2011

    with one half to

    Saul Perlmutter
    The Supernova Cosmology Project
    The DOE’s Lawrence Berkeley National Laboratory and The University of California-Berkeley,

    and the other half jointly to

    Brian P. Schmidt
    The High-z Supernova Search Team,
    The Australian National University, Weston Creek, Australia.

    and

    Adam G. Riess
    The High-z Supernova Search Team,The Johns Hopkins University and
    The Space Telescope Science Institute, Baltimore, MD.
    Written in the stars

    “Some say the world will end in fire, some say in ice…” *

    What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.

    In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.

    The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.

    The teams used a particular kind of supernova, called Type 1a supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.

    For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.

    The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.

    *Robert Frost, Fire and Ice, 1920
    ___________________________________________________________________
    To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called Dark Energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or Albert Einstein’s Theory of General Relativity must be replaced by a new theory of gravity on cosmic scales.

    The Dark Energy Survey is designed to probe the origin of the accelerating universe and help uncover the nature of Dark Energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the Dark Energy Survey collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.
    ___________________________________________________________________
    This is a very powerful telescope located on a mountain top in Chile. Over the years, it has surveyed about 1/8 of the sky and photographed over 300 million galaxies, many of which are so dim, they are about one-millionth as bright as the dimmest stars visible to the human eye. This telescope can image galaxies from the current day to as far back as eight billion years ago. Continuing with the analogy of a 50-year-old individual, DES can take pictures of the Universe starting when it was 21 years old up until the present. (Full disclosure: Researchers at Fermilab, where I also work, carried out this study — but I did not participate in this research.)

    As light from distant galaxies travels to Earth, it can be distorted by galaxies that are closer to us. By using these tiny distortions, astronomers have developed a very precise map of the distribution of matter in the cosmos. This map includes both ordinary matter, of which stars and galaxies are the most familiar examples, and dark matter, which is a hypothesized form of matter that neither absorbs nor emits light. Dark matter is only observed through its gravitational effect on other objects and is thought to be five times more prevalent than ordinary matter.
    __________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., and Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky.

    Coma cluster via NASA/ESA Hubble, the original example of Dark Matter discovered during observations by Fritz Zwicky and confirmed 30 years later by Vera Rubin.

    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970.

    Vera Rubin measuring spectra, worked on Dark Matter(Emilio Segre Visual Archives AIP SPL).

    Dark Matter Research

    Super Cryogenic Dark Matter Search from DOE’s SLAC National Accelerator Laboratory at Stanford University at SNOLAB (Vale Inco Mine, Sudbury, Canada).

    LBNL LZ Dark Matter Experiment xenon detector at Sanford Underground Research Facility Credit: Matt Kapust.


    DAMA at Gran Sasso uses sodium iodide housed in copper to hunt for dark matter LNGS-INFN.

    Yale HAYSTAC axion dark matter experiment at Yale’s Wright Lab.

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB (CA) deep in Sudbury’s Creighton Mine.

    The LBNL LZ Dark Matter Experiment Dark Matter project at SURF, Lead, SD.

    DAMA-LIBRA Dark Matter experiment at the Italian National Institute for Nuclear Physics’ (INFN’s) Gran Sasso National Laboratories (LNGS) located in the Abruzzo region of central Italy.

    DARWIN Dark Matter experiment. A design study for a next-generation, multi-ton dark matter detector in Europe at The University of Zurich [Universität Zürich](CH).

    PandaX II Dark Matter experiment at Jin-ping Underground Laboratory (CJPL) in Sichuan, China.

    Inside the Axion Dark Matter eXperiment U Washington. Credit: Mark Stone U. of Washington. Axion Dark Matter Experiment.

    3
    The University of Western Australia ORGAN Experiment’s main detector. A small copper cylinder called a “resonant cavity” traps photons generated during dark matter conversion. The cylinder is bolted to a “dilution refrigerator” which cools the experiment to very low temperatures.
    __________________________________

    Is the Big Bang incomplete?

    In order to test the Big Bang, astronomers can use measurements taken by the South Pole Telescope and use the theory to project forward to the present day. They can then take measurements from the Dark Energy Survey and compare them. If the measurements are accurate and the theory describes the cosmos, they should agree.

    And, by and large, they do — but not completely. When astronomers look at how “clumpy” the matter of the current Universe should be, purely from SPT measurements and extrapolations of theory, they find that the predictions are “clumpier” than current measurements by DES.

    This disagreement is potentially significant and could signal that the theory of the Big Bang is incomplete. Furthermore, this isn’t the first discrepancy that astronomers have encountered when they project measurements of the same primordial light imaged by the SPT to the modern day. Different research groups, using different telescopes, have found that the current Universe is expanding faster than expected from observations of the ancient light seen by the SPT, combined with Big Bang theory. This other discrepancy is called the Hubble Tension, named after American astronomer Edwin Hubble, who first realized that the Universe was expanding.

    __________________________________________________________________________________

    Edwin Hubble

    .

    __________________________________________________________________________________


    Have astronomers disproved the Big Bang?

    While the new discrepancy in predictions and measurements of the clumpiness of the Universe are preliminary, it could be that both this measurement and the Hubble Tension imply that the Big Bang theory might need some tweaking. Mind you, the discrepancies do not rise to the level of scrapping the theory entirely; however, it is the nature of the scientific method to adjust theories to account for new observations.

    See the full article here.

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 11:24 am on February 4, 2023 Permalink | Reply
    Tags: "Five ways that lasers shine a light on research and leadership in engineering and science", , , , , , ,   

    From Clemson University: “Five ways that lasers shine a light on research and leadership in engineering and science” 

    From Clemson University

    2.3.23

    Fig. 1: Image of the 124-m-high telecommunication tower of Säntis (Switzerland).
    1
    Also shown is the path of the laser recorded with its second harmonic at 515 nm.

    The news that lasers are capable of rerouting lightning [Nature Photonics (below)] and could someday be used to protect airports, launchpads and other infrastructure raised a question that has electrified some observers with curiosity:

    Just what else can these marvels of focused light do?

    We took that question to Clemson University’s John Ballato, one of the world’s leading optical scientists, and his answers might be—you guessed it—shocking.

    2
    John Ballato.

    3
    John Ballato, right, and Wade Hawkins work in their lab the Center for Optical Materials Science and Engineering Technologies (COMSET).

    Some lasers shine more intensely than the sun, while others can make things cold, he said. Lasers can drill the tiniest of holes, defend against missile attacks and help self-driving cars “see” where they are going, Ballato said. Those are just a few examples—and all have been the subject of research at Clemson.

    If anyone knows about how light and lasers are used, it’s Ballato, who holds the J.E. Sirrine Endowed Chair of Optical Fiber in the Department of Materials Science and Engineering at Clemson, with joint appointments in electrical engineering and in physics.

    He has authored more than 500 technical papers, holds 35 U.S. and international patents and is a fellow in seven professional organizations, including the American Association for the Advancement of Science.

    Ballato recently returned from San Francisco, where he served as a symposium chair at SPIE’s Photonics West LASE, “the most important laser technologies conference in the field,” according to its website.

    “We’ve got a great opportunity to shine a light—pun intended—on Clemson’s leadership in laser technology,” said Ballato, who was not involved in the lightning-related research. “Clemson has some of the world’s top talent in laser technology, unique facilities that include industry-scale capabilities for making some of the world’s most advanced optical fibers and opportunities for hands-on learning. If you want to be a leader, innovator or entrepreneur in lasers, Clemson is the place for you.”

    4
    Liang Dong, right, creates powerful lasers as part of his research at Clemson University.

    Ballato is among numerous researchers at Clemson who are doing seemingly miraculous things with laser light. Here are five things lasers can do (other than deflect lightening) that Clemson researchers are working with today.

    Ballato was part of an international team that developed the first laser self-cooling optical fiber made of silica glass and then turned that innovation into a laser amplifier. Researchers said it is a step toward self-cooling lasers. Such a laser would not need to be cooled externally because it would not heat up in the first place, they said, and it would produce exceptionally pure and stable frequencies. The work was led by researchers at Stanford University and originally reported in the journal Optics Letters [below two papers].

    The light from lasers can be made to twist or spin as it travels from one point to another. This can be done by engineering the light’s “orbital angular momentum” and is central to research led by Eric Johnson, the PalmettoNet Endowed Chair in Optoelectronics, with help from several other researchers, including Joe Watkins, director of General Engineering. The technology could make it possible to channel through fog, murky water and thermal turbulence, potentially leading to new ways of communicating and gathering data.

    Some lasers are orders of magnitude more intense than the surface of the sun, thanks to specially designed optical fiber that confines that light to a fraction of the width of a human hair. These powerful laser devices can be used to shoot missiles out of the sky or to cut, drill, weld and mark a variety of materials in ways that conventional tools cannot. Lasers, for example, are used to cut Gorilla Glass on smartphones. Clemson researchers helping advance laser technology in this direction include: Ballato; Liang Dong, a professor of electrical and computer engineering; and Wade Hawkins, a research assistant professor of materials science and engineering.

    Lidar, which stands for Light Detection and Ranging, is a technology that employs pulsing laser beams to measure distance to objects or surfaces. For self-driving cars, lidar serves as the “eyes” that help vehicles navigate the streets. Lidar can also be used for mapping and surveying and measuring density, temperature, and other properties of the atmosphere. The technology has been employed in numerous projects at Clemson, including Deep Orange 12, an autonomous race car designed by automotive engineering graduate students.

    Lasers are also playing a role in helping develop clean energy sources. One of the major challenges in creating hydrogen-powered turbines is protecting the blades against heat and high-velocity steam so extreme it would vaporize many materials. A possible solution under study at Clemson would be to cover turbine blades with a special slurry and use a laser to sinter it one point at a time, creating a protective coating. The research is led by Fei Peng, an associate professor of materials science and engineering.

    Optics Letters 2020
    Optics Letters 2020
    Nature Photonics

    See the full article here.

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Ranked as the 27th best national public university by U.S. News & World Report, Clemson University is dedicated to teaching, research and service. Founded in 1889, we remain committed both to world-class research and a high quality of life. In fact, 92 percent of our seniors say they’d pick Clemson again if they had it to do over.

    Clemson’s retention and graduation rates rank among the highest in the country for public universities. We’ve been named among the “Best Public College Values” by Kiplinger Magazine in 2019, and The Princeton Review named us among the “Best Value Colleges” for 2020.

    Our beautiful college campus sits on 20,000 acres in the foothills of the Blue Ridge Mountains, along the shores of Lake Hartwell. And we also have research facilities and economic development hubs throughout the state of South Carolina — in Anderson, Blackville, Charleston, Columbia, Darlington, Georgetown, Greenville, Greenwood, and Pendleton.

    The research, outreach and entrepreneurial projects led by our faculty and students are driving economic development and improving quality of life in South Carolina and beyond. In fact, a recent study determined that Clemson has an annual $1.9 billion economic impact on the state.

    Just as founder Thomas Green Clemson intertwined his life with the state’s economic and educational development, the Clemson Family impacts lives daily with their teaching, research and service.
    How Clemson got its start
    University founders Thomas Green and Anna Calhoun Clemson had a lifelong interest in education, agricultural affairs and science.

    In the post-Civil War days of 1865, Thomas Clemson looked upon a South that lay in economic ruin, once remarking, “This country is in wretched condition, no money and nothing to sell. Everyone is ruined, and those that can are leaving.”

    Thomas Clemson’s death on April 6, 1888, set in motion a series of events that marked the start of a new era in higher education in South Carolina. In his will, he bequeathed the Fort Hill plantation and a considerable sum from his personal assets for the establishment of an educational institution that would teach scientific agriculture and the mechanical arts to South Carolina’s young people.

    Clemson Agricultural College formally opened as an all-male military school in July 1893 with an enrollment of 446. It remained this way until 1955 when the change was made to “civilian” status for students, and Clemson became a coeducational institution. In 1964, the college was renamed Clemson University as the state legislature formally recognized the school’s expanded academic offerings and research pursuits.

    More than a century after its opening, the University provides diverse learning, research facilities and educational opportunities not only for the people of the state — as Thomas Clemson dreamed — but for thousands of young men and women throughout the country and the world.

     
  • richardmitnick 10:46 am on February 4, 2023 Permalink | Reply
    Tags: "Untangling a Knot of Galaxy Clusters", Abell 2256, , , , , , ,   

    From The National Aeronautics and Space Administration Chandra X-ray telescope: “Untangling a Knot of Galaxy Clusters” 

    NASA Chandra Banner

    From The National Aeronautics and Space Administration Chandra X-ray telescope

    1.30.23

    1
    Abell 2256, Labeled (Credit: X-ray: Chandra: NASA/CXC/Univ. of Bolonga/K. Rajpurohit et al.; XMM-Newton: ESA/XMM-Newton/Univ. of Bolonga/K. Rajpurohit et al.
    Radio: LOFAR: LOFAR/ASTRON; GMRT: NCRA/TIFR/GMRT; VLA: NSF/NRAO/VLA; Optical/IR: Pan-STARRS

    Astronomers have captured a spectacular, ongoing collision between at least three galaxy clusters. Data from NASA’s Chandra X-ray Observatory, ESA’s (European Space Agency’s) XMM-Newton, and a trio of radio telescopes is helping astronomers sort out what is happening in this jumbled scene.

    The European Space Agency [La Agencia Espacial Europea] [Agencia Espacial Europea][Agence spatiale européenne][Europäische Weltraumorganization](EU) XMM Newton X-ray Telescope.

    Collisions and mergers like this are the main way that galaxy clusters can grow into the gigantic cosmic edifices seen today. These also act as the largest particle accelerators in the universe.

    The giant galaxy cluster forming from this collision is Abell 2256, located 780 million light-years from Earth. This composite image of Abell 2256 combines X-rays from Chandra and XMM in blue with radio data collected by the Giant Metrewave Radio Telescope (GMRT), the Low Frequency Array (LOFAR), and the Karl G. Jansky Very Large Array (VLA) all in red, plus optical and infrared data from Pan-STARRs in white and pale yellow.

    Astronomers studying this object are trying to tease out what has led to this unusual-looking structure. Each telescope tells a different part of the story. Galaxy clusters are some of the biggest objects in the universe containing hundreds or even thousands of individual galaxies. In addition, they contain enormous reservoirs of superheated gas, with temperatures of several million degrees Fahrenheit. Only X-ray telescopes like Chandra and XMM can see this hot gas. A labeled version of the figure shows gas from two of the galaxy clusters, with the third blended too closely to separate from the others.

    The radio emission in this system arises from an even more complex set of sources. The first are the galaxies themselves, in which the radio signal is generated by particles blasting away in jets from supermassive black holes at their centers. These jets are either shooting into space in straight and narrow lines (those labeled “C” and “I” in the annotated image, using the astronomer’s naming system) or slowed down as the jets interact with gas they are running into, creating complex shapes and filaments (“A”, “B,” and “F”). Source F contains three sources, all created by a black hole in a galaxy aligning with the left-most source of this trio.

    Radio waves are also coming from huge filamentary structures (labeled “relic”), mostly located to the north of the radio-emitting galaxies, likely generated when the collision created shock waves and accelerated particles in the gas across over two million light-years. A paper analyzing this structure was published earlier this year by Kamlesh Rajpurohit from the University of Bologna in Italy in the March 2022 issue of The Astrophysical Journal [below]. This is Paper I in an ongoing series studying different aspects of this colliding galaxy cluster system.

    Finally, there is a “halo” of radio emission located near the center of the collision. Because this halo overlaps with the X-ray emission and is dimmer than the filamentary structure and the galaxies, another radio image has been produced to emphasize the faint radio emission. Paper II led by Rajpurohit, recently published in the journal Astronomy and Astrophysics [below], presents a model that the halo emission may be caused by the reacceleration of particles by rapid changes in the temperature and density of the gas as the collision and merging of the clusters proceed. This model, however, is unable to explain all the features of the radio data, highlighting the need for more theoretical study of this and similar objects.

    2
    Halo of Radio Emission (Credit: LOFAR/ASTRON)

    Paper III by Rajpurohit and collaborators will study the galaxies producing radio waves in Abell 2256. This cluster contains an unusually large number of such galaxies, possibly because the collision and merger are triggering the growth of supermassive black holes and consequent eruptions. More details about the LOFAR image of Abell 2256 will be reported in an upcoming paper by Erik Osinga.

    The full list of co-authors for papers I and II include researchers from the University of Bologna, Italy (Franco Vazza, Annalisa Bonafede, Andrea Botteon, Christopher J. Riseley, Paola Domínguez-Fernández, Chiara Stuardi, and Daniele Dallacasa); Leiden Observatory, Leiden University, the Netherlands (Erik Osinga, Reinout J. van Weeren, Timothy Shimwell, Huub Röttgering, and George Miley); Thüringer Landessternwarte, Tautenburg, Germany (Matthias Hoeft and Alexander Drabent); INAF-Istituto di Radio Astronomia, Bologna, Italy (Gianfranco Brunetti and Rossella Cassano); Hamburger Sternwarte, Germany (Denis Wittor, Marcus Brüggen, and Francesco de Gasperin); Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Italy (Marisa Brienza); Center for Astrophysics, Harvard | Smithsonian (William Forman); Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley (Sangeeta Rajpurohit); Physical Research Laboratory, Ahmedabad, India (Arvind Singh Rajpurohit); Universität Würzburg, Würzburg, Germany (Etienne Bonnassieux), and INAF–IASF Milano, Italy (Mariachiara Rossetti).

    The Astrophysical Journal 2022
    Astronomy and Astrophysics 2023

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.
    In 1976 the Chandra X-ray Observatory (called AXAF at the time) was proposed to National Aeronautics and Space Administration by Riccardo Giacconi and Harvey Tananbaum. Preliminary work began the following year at NASA’s Marshall Space Flight Center and the Harvard Smithsonian Center for Astrophysics. In the meantime, in 1978, NASA launched the first imaging X-ray telescope, Einstein (HEAO-2), into orbit. Work continued on the AXAF project throughout the 1980s and 1990s. In 1992, to reduce costs, the spacecraft was redesigned. Four of the twelve planned mirrors were eliminated, as were two of the six scientific instruments. AXAF’s planned orbit was changed to an elliptical one, reaching one third of the way to the Moon’s at its farthest point. This eliminated the possibility of improvement or repair by the space shuttle but put the observatory above the Earth’s radiation belts for most of its orbit. AXAF was assembled and tested by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, California.

    AXAF was renamed Chandra as part of a contest held by NASA in 1998, which drew more than 6,000 submissions worldwide. The contest winners, Jatila van der Veen and Tyrel Johnson (then a high school teacher and high school student, respectively), suggested the name in honor of Nobel Prize–winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. He is known for his work in determining the maximum mass of white dwarf stars, leading to greater understanding of high energy astronomical phenomena such as neutron stars and black holes. Fittingly, the name Chandra means “moon” in Sanskrit.

    Originally scheduled to be launched in December 1998, the spacecraft was delayed several months, eventually being launched on July 23, 1999, at 04:31 UTC by Space Shuttle Columbia during STS-93. Chandra was deployed from Columbia at 11:47 UTC. The Inertial Upper Stage’s first stage motor ignited at 12:48 UTC, and after burning for 125 seconds and separating, the second stage ignited at 12:51 UTC and burned for 117 seconds. At 22,753 kilograms (50,162 lb), it was the heaviest payload ever launched by the shuttle, a consequence of the two-stage Inertial Upper Stage booster rocket system needed to transport the spacecraft to its high orbit.

    Chandra has been returning data since the month after it launched. It is operated by the SAO at the Chandra X-ray Center in Cambridge, Massachusetts, with assistance from Massachusetts Institute of Technology and Northrop Grumman Space Technology. The ACIS CCDs suffered particle damage during early radiation belt passages. To prevent further damage, the instrument is now removed from the telescope’s focal plane during passages.

    Although Chandra was initially given an expected lifetime of 5 years, on September 4, 2001, NASA extended its lifetime to 10 years “based on the observatory’s outstanding results.” Physically Chandra could last much longer. A 2004 study performed at the Chandra X-ray Center indicated that the observatory could last at least 15 years.

    In July 2008, the International X-ray Observatory, a joint project between European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU), NASA and Japan Aerospace Exploration Agency (JAXA) (国立研究開発法人宇宙航空研究開発機構], was proposed as the next major X-ray observatory but was later cancelled. ESA later resurrected a downsized version of the project as the Advanced Telescope for High Energy Astrophysics (ATHENA), with a proposed launch in 2028.

    European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU) Athena spacecraft depiction

    On October 10, 2018, Chandra entered safe mode operations, due to a gyroscope glitch. NASA reported that all science instruments were safe. Within days, the 3-second error in data from one gyro was understood, and plans were made to return Chandra to full service. The gyroscope that experienced the glitch was placed in reserve and is otherwise healthy.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [NASA/ESA Hubble, NASA Chandra, NASA Spitzer, and associated programs.] NASA shares data with various national and international organizations such as from [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 9:19 am on February 4, 2023 Permalink | Reply
    Tags: "HGC": High-Granularity Calorimeter, "Prototype Particle Detector Project Smashes Milestone", , , , , Carnegie Mellon University physicists are one step closer to a major upgrade for the Large Hadron Collider's Compact Muon Solenoid experiment., , , , ,   

    From Carnegie Mellon University: “Prototype Particle Detector Project Smashes Milestone” 

    From Carnegie Mellon University

    1.31.23
    Jocelyn Duffy
    Mellon College of Science
    jhduffy@andrew.cmu.edu
    412-268-9982

    Carnegie Mellon University physicists are one step closer to a major upgrade for the Large Hadron Collider’s Compact Muon Solenoid experiment.

    1
    A team based in the Department of Physics has built and tested prototypes for the High-Granularity Calorimeter (HGC), an upgrade to the current Compact Muon Solenoid detector at CERN’s Large Hadron Collider. The team includes, from left, first row: Amy Germer, a senior in physics and mathematical sciences; Valentina Dutta, an assistant professor; second row: John Alison, an assistant professor; Sindhu Murthy, a doctoral student; Manfred Paulini, a professor of physics; third row: Eric Day, a technician; Jessica Parshook, an engineer on the project; Patrick Bryant, a research associate; and Andrew Roberts, a doctoral student. Credit: CMU.

    A team led by John Alison, an assistant professor in physics, and Manfred Paulini, a professor of physics and the Mellon College of Science associate dean for faculty and graduate affairs, has successfully built and tested prototypes for the High-Granularity Calorimeter (HGC), an upgrade to the current CMS detector. On the one hand, building functional prototypes is a major milestone several years in the making. On the other hand, the milestone is the first step in a manufacturing project that will take place over the next three years.

    “CMS can be thought of as a large 3D camera that records the products of the proton-proton collisions provided by the LHC,” Alison said. “For example, images collected from the detector were used to discover the Higgs boson in 2012.”

    Since the discovery of the Higgs boson, a major focus of the particle physics has been in studying the properties of the Higgs boson in detail and searching for new particles not predicted by the standard model of particle physics.

    Comparing measurements to predictions will allow new theories to be tested but more data is needed.

    The LHC has a 15-year program to increase the total number of proton collisions by a factor of 20. This program requires collecting more data faster and comes at a significant cost: increased radiation. In addition to producing new exotic states of matter — like the Higgs boson — LHC proton collisions produce large amounts of ionizing radiation. This radiation is similar to that produced by a nuclear reactor and is damaging to people and the instrumentation that makes up the detector.

    Built almost 20 years ago, the current CMS detector was not designed to handle the amount of radiation damage anticipated during future LHC runs. New, upgraded detectors are needed both to improve the quality of the recorded images and cope with the more challenging radiation environment. This is where the High-Granularity Calorimeter upgrade comes in.

    2
    High-Granularity Calorimeter. Credit: CERN.

    Big Data Gets Bigger

    The HGC will replace current CMS detectors in regions that face the most radiation. A next-generation imaging calorimeter, the HGC will significantly increase the precision with which the LHC collisions are imaged. The number of individual measurements per picture will increase from about 20,000 in current detectors to about 6 million in the HGC. The measurements of individual particles will go from the handful of numbers that the current detector provides to a high-resolution 3D movie of how the particles interact when traversing the detector.

    The HGC will be built in the next five years, and Carnegie Mellon is playing a leading role in its construction. The HGC will be composed of 30,000 20-centimeter hexagonal modules. The modules — essentially radiation tolerant digital cameras — will be tiled to form wheels several meters in diameter. The wheels will then be stacked to form the full 3D detector. In total, the HGC will require 600 square meters of active silicon sensors.

    Alison, Paulini and Valentina Dutta, a new assistant professor in physics, will build and test 5,000 of these modules in Wean Hall laboratory with the help of engineers, technicians and students. The remaining modules will be produced by CMS collaborators at The University of California-Santa Barbara and Texas Tech University in the U.S., and by groups in China, India and Taiwan. Each module consists of a silicon sensor attached to a printed circuit board housing readout electronics and to a base plate, which provides overall stability.

    3

    Module construction will be performed with a series of automated robots that use pattern-recognition algorithms for assembly and then the required approximately 500 electrical connections per module are established. After a series of testing at CMU the modules are tiled onto wheels at Fermilab — a particle physics lab outside of Chicago — and then sent to CERN in Switzerland for installation in the CMS detector.

    The production of the first working modules this fall was part of a qualifying exercise in which the various assembly centers demonstrated that they are ready and able to build the high-quality modules needed by HGC.

    The CMU group established a class 1,000 clean room on the eighth floor of Wean Hall, expanding an existing space used by the medium-energy physics group. They have installed and commissioned an 8,000-pound gantry robot to attach the different module layers and an automated wire bonder to make the electrical connections within the modules. The prototype modules allowed the group to test its automated assembly procedures and exercise the full production chain.

    “It is great to see our group achieving this qualification milestone,” Paulini said. “I had been working diligently for some years to bring this project to CMU since it also offers opportunities for graduate and especially undergraduate students to obtain hands-on instrumentation experience working in our lab during the semester or for summer research.”

    Producing a handful of modules to specification is just the beginning. During full-scale module production — starting in 2024 — CMU will produce 12 modules per day until early 2026. A major challenge in ramping throughput will be recruiting and onboarding local talent.

    “To meet production needs we have to grow the group with hiring four more full-time technicians and engineers who will work on the daily production line,” said Jessica Parshook, the lead engineer for Carnegie Mellon’s project team.

    Developing and implementing reliable test procedures for quality control is another major challenge going forward. The production pipeline requires several days to build each module. Catching and fixing any flaws in production quickly will be critical. Postdoctoral fellows and graduate students will create most of the assembly and quality control procedures that will provide opportunities for a significant number of CMU undergraduates to get hands-on experience testing modern particle physics detectors.

    “Our efforts here could lead to the next big discovery in physics and that excites me,” said Sindhu Murthy, a doctoral student in physics. “In these early stages of setting up production, I get to see the different aspects of an engineering project of this scale. It’s a great experience and a privilege to contribute to this upgrade. I’m always thinking about how we can optimize module assembly so that everything goes as planned.”

    Alison, Dutta and Paulini said that recent advances in image processing from machine learning will be crucial in assuring quality control during production.

    “This work, a mix of computer science, machine learning and robotics, is a perfect fit for CMU and we plan to tap into resources throughout the university,” Alison said.

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Mellon University is a global research university with more than 12,000 students, 95,000 alumni, and 5,000 faculty and staff.

    Carnegie Mellon University has been a birthplace of innovation since its founding in 1900.

    Today, we are a global leader bringing groundbreaking ideas to market and creating successful startup businesses.

    Our award-winning faculty members are renowned for working closely with students to solve major scientific, technological and societal challenges. We put a strong emphasis on creating things—from art to robots. Our students are recruited by some of the world’s most innovative companies.

    We have campuses in Pittsburgh, Qatar and Silicon Valley, and degree-granting programs around the world, including Africa, Asia, Australia, Europe and Latin America.

    The Carnegie Mellon University was established by Andrew Carnegie as the Carnegie Technical Schools, the university became the Carnegie Institute of Technology in 1912 and began granting four-year degrees. In 1967, the Carnegie Institute of Technology merged with the Mellon Institute of Industrial Research, formerly a part of the The University of Pittsburgh. Since then, the university has operated as a single institution.

    The Carnegie Mellon University has seven colleges and independent schools, including the College of Engineering, College of Fine Arts, Dietrich College of Humanities and Social Sciences, Mellon College of Science, Tepper School of Business, Heinz College of Information Systems and Public Policy, and the School of Computer Science. The Carnegie Mellon University has its main campus located 3 miles (5 km) from Downtown Pittsburgh, and the university also has over a dozen degree-granting locations in six continents, including degree-granting campuses in Qatar and Silicon Valley.

    Past and present faculty and alumni include 20 Nobel Prize laureates, 13 Turing Award winners, 23 Members of the American Academy of Arts and Sciences, 22 Fellows of the American Association for the Advancement of Science , 79 Members of the National Academies, 124 Emmy Award winners, 47 Tony Award laureates, and 10 Academy Award winners. Carnegie Mellon enrolls 14,799 students from 117 countries and employs 1,400 faculty members.

    Research

    Carnegie Mellon University is classified among “R1: Doctoral Universities – Very High Research Activity”. For the 2006 fiscal year, the Carnegie Mellon University spent $315 million on research. The primary recipients of this funding were the School of Computer Science ($100.3 million), the Software Engineering Institute ($71.7 million), the College of Engineering ($48.5 million), and the Mellon College of Science ($47.7 million). The research money comes largely from federal sources, with a federal investment of $277.6 million. The federal agencies that invest the most money are the National Science Foundation and the Department of Defense, which contribute 26% and 23.4% of the total Carnegie Mellon University research budget respectively.

    The recognition of Carnegie Mellon University as one of the best research facilities in the nation has a long history—as early as the 1987 Federal budget Carnegie Mellon University was ranked as third in the amount of research dollars with $41.5 million, with only Massachusetts Institute of Technology and Johns Hopkins University receiving more research funds from the Department of Defense.

    The Pittsburgh Supercomputing Center is a joint effort between Carnegie Mellon University, University of Pittsburgh, and Westinghouse Electric Company. Pittsburgh Supercomputing Center was founded in 1986 by its two scientific directors, Dr. Ralph Roskies of the University of Pittsburgh and Dr. Michael Levine of Carnegie Mellon. Pittsburgh Supercomputing Center is a leading partner in the TeraGrid, The National Science Foundation’s cyberinfrastructure program.

    Scarab lunar rover is being developed by the RI.

    The Robotics Institute (RI) is a division of the School of Computer Science and considered to be one of the leading centers of robotics research in the world. The Field Robotics Center (FRC) has developed a number of significant robots, including Sandstorm and H1ghlander, which finished second and third in the DARPA Grand Challenge, and Boss, which won the DARPA Urban Challenge. The Robotics Institute has partnered with a spinoff company, Astrobotic Technology Inc., to land a CMU robot on the moon by 2016 in pursuit of the Google Lunar XPrize. The robot, known as Andy, is designed to explore lunar pits, which might include entrances to caves. The RI is primarily sited at Carnegie Mellon University ‘s main campus in Newell-Simon hall.

    The Software Engineering Institute (SEI) is a federally funded research and development center sponsored by the U.S. Department of Defense and operated by Carnegie Mellon University, with offices in Pittsburgh, Pennsylvania, USA; Arlington, Virginia, and Frankfurt, Germany. The SEI publishes books on software engineering for industry, government and military applications and practices. The organization is known for its Capability Maturity Model (CMM) and Capability Maturity Model Integration (CMMI), which identify essential elements of effective system and software engineering processes and can be used to rate the level of an organization’s capability for producing quality systems. The SEI is also the home of CERT/CC, the federally funded computer security organization. The CERT Program’s primary goals are to ensure that appropriate technology and systems management practices are used to resist attacks on networked systems and to limit damage and ensure continuity of critical services subsequent to attacks, accidents, or failures.

    The Human–Computer Interaction Institute (HCII) is a division of the School of Computer Science and is considered one of the leading centers of human–computer interaction research, integrating computer science, design, social science, and learning science. Such interdisciplinary collaboration is the hallmark of research done throughout the university.

    The Language Technologies Institute (LTI) is another unit of the School of Computer Science and is famous for being one of the leading research centers in the area of language technologies. The primary research focus of the institute is on machine translation, speech recognition, speech synthesis, information retrieval, parsing and information extraction. Until 1996, the institute existed as the Center for Machine Translation that was established in 1986. From 1996 onwards, it started awarding graduate degrees and the name was changed to Language Technologies Institute.

    Carnegie Mellon is also home to the Carnegie School of management and economics. This intellectual school grew out of the Tepper School of Business in the 1950s and 1960s and focused on the intersection of behavioralism and management. Several management theories, most notably bounded rationality and the behavioral theory of the firm, were established by Carnegie School management scientists and economists.

    Carnegie Mellon also develops cross-disciplinary and university-wide institutes and initiatives to take advantage of strengths in various colleges and departments and develop solutions in critical social and technical problems. To date, these have included the Cylab Security and Privacy Institute, the Wilton E. Scott Institute for Energy Innovation, the Neuroscience Institute (formerly known as BrainHub), the Simon Initiative, and the Disruptive Healthcare Technology Institute.

    Carnegie Mellon has made a concerted effort to attract corporate research labs, offices, and partnerships to the Pittsburgh campus. Apple Inc., Intel, Google, Microsoft, Disney, Facebook, IBM, General Motors, Bombardier Inc., Yahoo!, Uber, Tata Consultancy Services, Ansys, Boeing, Robert Bosch GmbH, and the Rand Corporation have established a presence on or near campus. In collaboration with Intel, Carnegie Mellon has pioneered research into claytronics.

     
  • richardmitnick 8:12 am on February 4, 2023 Permalink | Reply
    Tags: "Astronomers Studied More Than 5000 Black Holes to Figure Out Why They Twinkle", , , , , ,   

    From “The Conversation (AU)” : “Astronomers Studied More Than 5000 Black Holes to Figure Out Why They Twinkle” 

    From “The Conversation (AU)”

    2.4.23
    Christian Wolf

    Black holes are bizarre things, even by the standards of astronomers. Their mass is so great it bends space around them so tightly that nothing can escape, even light itself.

    And yet, despite their famous blackness, some black holes are quite visible. The gas and stars these galactic vacuums devour are sucked into a glowing disc before their one-way trip into the hole, and these discs can shine more brightly than entire galaxies.

    Stranger still, these black holes twinkle.

    1
    This illustration shows a disk of hot gas swirling around a black hole. The stream of gas stretching to the right is what remains of a star that was pulled apart by the black hole. Credit: NASA/JPL-Caltech.

    The brightness of the glowing discs can fluctuate from day to day, and nobody is entirely sure why.

    We piggy-backed on NASA’s asteroid defense effort to watch more than 5,000 of the fastest-growing black holes in the sky for five years in an attempt to understand why this twinkling occurs.

    In a new paper in Nature Astronomy [below], we report our answer: a kind of turbulence driven by friction and intense gravitational and magnetic fields.

    Gigantic star-eaters

    We study supermassive black holes, the kind that sit at the centers of galaxies and are as massive as millions or billions of Suns.

    Our own galaxy, the Milky Way, has one of these giants at its center, with a mass of about four million Suns.

    For the most part, the 200 billion or so stars that make up the rest of the galaxy (including our Sun) happily orbit around the black hole at the center.

    However, things are not so peaceful in all galaxies. When pairs of galaxies pull on each other via gravity, many stars may end up tugged too close to their galaxy’s black hole. This ends badly for the stars: They are torn apart and devoured.

    We are confident this must have happened in galaxies with black holes that weigh as much as a billion Suns, because we can’t imagine how else they could have grown so large. It may also have happened in the Milky Way in the past.

    Black holes can also feed in a slower, more gentle way: by sucking in clouds of gas blown out by geriatric stars known as red giants.

    Feeding time

    In our new study, we looked closely at the feeding process among the 5,000 fastest-growing black holes in the Universe.

    In earlier studies, we discovered the black holes with the most voracious appetite. Last year, we found a black hole that eats an Earth’s-worth of stuff every second [PASA (below)]. In 2018, we found one that eats a whole Sun every 48 hours [PASA (below)].

    But we have lots of questions about their actual feeding behavior. We know material on its way into the hole spirals into a glowing “accretion disc” that can be bright enough to outshine entire galaxies. These visibly feeding black holes are called quasars.

    Most of these black holes are a long, long way away – much too far for us to see any detail of the disc. We have some images of accretion discs around nearby black holes, but they are merely breathing in some cosmic gas rather than feasting on stars.

    Five years of flickering black holes

    In our new work, we used data from NASA’s ATLAS telescope in Hawaii.


    It scans the entire sky every night (weather permitting), monitoring for asteroids approaching Earth from the outer darkness.

    These whole-sky scans also happen to provide a nightly record of the glow of hungry black holes, deep in the background. Our team put together a five-year movie of each of those black holes, showing the day-to-day changes in brightness caused by the bubbling and boiling glowing maelstrom of the accretion disc.

    The twinkling of these black holes can tell us something about accretion discs.

    In 1998, astrophysicists Steven Balbus and John Hawley proposed a theory of “magneto-rotational instabilities” that describes how magnetic fields can cause turbulence in the discs [Reviews of Modern Physics (below)]. If that is the right idea, then the discs should sizzle in regular patterns.

    They would twinkle in random patterns that unfold as the discs orbit. Larger discs orbit more slowly with a slow twinkle, while tighter and faster orbits in smaller discs twinkle more rapidly.

    But would the discs in the real world prove this simple, without any further complexities? (Whether “simple” is the right word for turbulence in an ultra-dense, out-of-control environment embedded in intense gravitational and magnetic fields where space itself is bent to breaking point is perhaps a separate question.)

    Using statistical methods, we measured how much the light emitted from our 5,000 discs flickered over time. The pattern of flickering in each one looked somewhat different.

    But when we sorted them by size, brightness, and color, we began to see intriguing patterns. We were able to determine the orbital speed of each disc – and once you set your clock to run at the disc’s speed, all the flickering patterns started to look the same.

    This universal behavior is indeed predicted by the theory of “magneto-rotational instabilities”.

    That was comforting! It means these mind-boggling maelstroms are “simple” after all.

    And it opens new possibilities. We think the remaining subtle differences between accretion discs occur because we are looking at them from different orientations.

    The next step is to examine these subtle differences more closely and see whether they hold clues to discern a black hole’s orientation. Eventually, our future measurements of black holes could be even more accurate.

    Nature Astronomy 2022
    PASA 2022
    PASA 2018
    See the above science papers for instructive material with images.
    Reviews of Modern Physics 1998

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 6:38 pm on February 3, 2023 Permalink | Reply
    Tags: "New Method to Weigh Protoplanetary Disks", , Astronomers have found a way to directly measure the amount of gas in protoplanetary disks without making assumptions about the relative amounts of different gasses-a more method., , , ,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array](CL) : “New Method to Weigh Protoplanetary Disks” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array](CL)

    1.17.23 [Previously reported from NAOJ]

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory Santiago – Chile
    Phone: +56 2 2467 6258
    Cell phone: +56 9 7587 1963
    Email: valeria.foncea@alma.cl

    Daisuke Iono
    Interim EA ALMA EPO officer
    Observatory, Tokyo – Japan
    Email: d.iono@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    1
    Observational image of the protoplanetary disk around TW Hydrae showing the distributions of solid particles (red), carbon monoxide (blue), and dense gas (white). Credit: T. Yoshida, T. Tsukagoshi et al. – ALMA (ESO/NAOJ/NRAO)

    Astronomers have found a way to directly measure the amount of gas in protoplanetary disks without making assumptions about the relative amounts of different types of gas, making this method more accurate and robust than previous methods.

    Planets form in protoplanetary disks of gas and dust around young stars. Scientists study protoplanetary disks by looking at their spectra, the wavelengths of radio waves emitted by disk components. Hydrogen gas is the main constituent of protoplanetary disks, but it isn’t easy to measure directly because it doesn’t emit radio waves efficiently. Carbon monoxide is often used as a proxy. Still, the hydrogen-to-carbon monoxide ratio can differ depending on the environment, leading to significant uncertainties in total mass estimates.

    A team led by Tomohiro Yoshida, a graduate student at the Graduate University for Advanced Studies in Japan, searched the Atacama Large Millimeter/submillimeter Array (ALMA) archival data for observations of the nearest protoplanetary disk around the star TW Hydrae. From this, they produced a radio image 15 times more sensitive than previous studies, allowing them to examine the wavelengths of the spectral lines and their shapes.

    From the shape of the carbon monoxide lines, the team could measure the gas pressure near the disk’s center. This pressure reveals the total mass of gas near the center without making assumptions about the hydrogen-to-carbon monoxide ratio. The team found that despite being near the end of the planet formation process, there is still enough gas in the inner region of the TW Hydrae system to make a Jupiter-sized planet.

    Yoshida, the lead author of this study, says, “We would like to apply this novel technique to other disks and investigate the amount of gas in planet-forming disks with various characteristics and at various ages to clarify the gas dissipation process and the formation process of planetary systems.”

    Additional Information

    These results appeared in The Astrophysical Journal Letters on September 22, 2022.
    See the science paper for instructive material with images.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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  • richardmitnick 5:57 pm on February 3, 2023 Permalink | Reply
    Tags: "Outflows from Baby Star Affect Nearby Star Formation", , , , , , These observations have succeeded in directly imaging the impact of molecular outflows on star formation within a star forming cluster.   

    From ALMA [The Atacama Large Millimeter/submillimeter Array](CL) : “Outflows from Baby Star Affect Nearby Star Formation” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array](CL)

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory Santiago – Chile
    Phone: +56 2 2467 6258
    Cell phone: +56 9 7587 1963
    Email: valeria.foncea@alma.cl

    Junko Ueda
    Public Information Officer
    NAOJ
    Email: junko.ueda@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    2.3.23

    1
    Composite image of the cluster forming region, OMC-2/ FIR 3 and FIR 4, obtained with ALMA (red: carbon monoxide gas, orange: emission from the dust, blue: silicon monoxide gas). For each color, the stronger the radio wave intensity, the more whitish the color is. FIR 3 is located in the upper left of this image, while FIR 4 is located in the bottom right. The giant molecular outflow driven by the protostar in the FIR 3 region (red color) collides with the “filamentary molecular cloud” (orange color). Subsequently, outflow gas interacting with the filamentary molecular cloud is being compressed (shown in pinkish red). The outflow gas also collides with downstream dense gas (shown in orange color) where a group of baby stars is being born (green circles within the FIR 4 region). The shock layers are observed with the silicon monoxide gas (pale blue). The white bar in the lower right corner shows the scale of 4000 astronomical units (au). Credit: A. Sato et al./ALMA (ESO/NAOJ/NRAO).

    2
    Composite image of the cluster forming region, OMC-2/ FIR 3 and FIR 4, obtained with ALMA (red: carbon monoxide gas, orange: emission from the dust, blue: silicon monoxide gas). For each color, the stronger the radio wave intensity, the more whitish the color is. FIR 3 is located in the upper left of this image, while FIR 4 is located in the bottom right. The giant molecular outflow driven by the protostar in the FIR 3 region (red color) collides with the “filamentary molecular cloud” (orange color). Subsequently, outflow gas interacting with the filamentary molecular cloud is being compressed (shown in pinkish red). The outflow gas also collides with downstream dense gas (shown in orange color) where a group of baby stars is being born (green circles within the FIR 4 region). The shock layers are observed with the silicon monoxide gas (pale blue). The white bar in the lower right corner shows the scale of 4000 astronomical units (au). Credit: A. Sato et al./ALMA (ESO/NAOJ/NRAO)

    Astronomers revealed fast gas outflows from a baby star strongly colliding with nearby dense gas where a group of baby stars are being born. The result suggests that the outflow collision shakes the cradle of the baby stars, and has a significant impact on the ongoing star formation process. This study provides insight into the star formation process within cluster regions where baby stars are born simultaneously in a complex and crowded environment.

    Baby stars (protostars) form due to the collapse of dense cores of gas and dust. At the same time, some of the material is ejected by the protostar. This phenomenon is called molecular outflow and shows a bipolar and collimated structure. The extension of the molecular outflow can be more than a million times bigger than the protostar. The molecular outflow is much easier to find than the compact and embedded protostar itself, hence searching for outflows can be a powerful tool to explore the birthplaces of protostars.

    The majority of stars form together with other stars in a crowded environment called a cluster formation. Theoretical studies predict that the outflows within the star forming cluster play an important role and can themself trigger (or at least facilitate) further star-formation activity. Alternatively, ongoing star formation could be disrupted by neighboring molecular outflows. Although star formation in a cluster environment is common, observational studies that spatially resolve the individual protostars within the cluster are still limited because the target sources are located relatively far from us. ALMA (Atacama Large Millimeter/submillimeter Array) is a powerful instrument to resolve gas and dust distributions and reveal the complex star formation processes in cluster forming regions.

    Asako Sato, a graduate student at Kyushu University in Japan, and her team used ALMA to observe the regions FIR 3 and FIR 4 in the Orion Molecular Cloud -2 (OMC-2). OMC-2 is one of the nearest cluster forming regions, located at the distance of 1400 light-years away in the constellation Orion. They investigated the spatial distribution of dust and the gaseous carbon monoxide (CO) and silicon monoxide (SiO). The dust is one of the fundamental compositions to form dense material, hence a good tracer of dense cores, where protostar formation happens. CO is the second most abundant molecule in the Universe after the hydrogen molecule. CO emits strong signals in the millimeter wavelength regime and is a good tracer of molecular outflows. Emission from SiO is used to trace powerful shocked regions. A collision such as between bipolar molecular outflows and surrounding material strips silicon (Si) atoms from dust grains, which then react with oxygen (O) to form SiO. Thanks to ALMA’s high-sensitivity, this study detected twice as many molecular outflows as compared to the previous studies in the FIR 3 and FIR 4 regions.

    The results show a giant molecular outflow driven by a protostar in the FIR 3 region strongly colliding with the FIR 4 region, where several protostars are being formed. The ALMA observations have clearly imaged shock layers between the molecular outflow and dense materials associated with the FIR 4 region. “The molecular outflow is proceeding from the upper left of the image, and colliding with the FIR 4 region in the bottom right. We clearly see two strong shock layers in SiO gas (which is denoted in blue color in Figure 2 within the FIR 4 region).” says Satoko Takahashi, an astronomer at the National Astronomical Observatory of Japan, and co-author of the paper. Moreover, the image shows that the CO gas within the outflow collides with the “filamentary molecular cloud” (Figure 2: presented in orange color) and is subsequently compressed (Figure 2: shown in pinkish red). The team also obtained evidence that dust within the filamentary molecular clouds can be heated by a collision with the molecular outflow. Finally, within the compressed clouds, the team detected fragmented dusty sources, which could be the cradles of the future star formation sites.

    With this study, it was difficult to conclude whether star formation activities within the cluster forming region, FIR 4, were triggered by the collision with the giant molecular outflow, or if the star formation within FIR 4 had already started before the collision. “Even though the two different star formation scenarios were not disentangled, the observations clearly indicated strong shocks caused by the outflow colliding with the FIR 4 region. This means the collision must have affected the star forming activities there.” Says Sato, the primary author of the paper. She also expresses her ambition to perform future observations with ALMA to answer the questions, “How protostars in the FIR 4 region will evolve and how massive stars will form can be investigated through the dynamical motions of the gas compressed by the giant bipolar molecular outflow, which could indicate the inflow of gas toward the center of the cluster or alternatively the destruction of the cradle of the cluster.”

    These observations have succeeded in directly imaging the impact of molecular outflows on star formation within a star forming cluster. Further studies will help us to understand the star formation process under the cluster forming environment.

    Additional Information

    This research was published in The Astrophysical Journal on February 2, 2023.

    Authors: Asako Sato (Kyushu University), Satoko Takahashi (NAOJ/SOKENDAI), Shun Ishii (NAOJ/SOKENDAI), Paul T. P. Ho (ASIAA/EAO), Masahiro N. Machida (Kyushu University), John Carpenter (JAO), Luis A. Zapata (UNAM), Paula Stella Teixeira (University of St Andrews), and Sumeyye Suri (University of Vienna).

    See the full article here.

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    NRAO Small
    ESO 50 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

     
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