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  • richardmitnick 7:32 pm on September 23, 2020 Permalink | Reply
    Tags: "Five mysteries the Standard Model can’t explain", 1. Why do neutrinos have mass?, 2. What is dark matter?, 3. Why is there so much matter in the universe?, 4. Why is the expansion of the universe accelerating?, 5. Is there a particle associated with the force of gravity?, More to explore,   

    From Symmetry: “Five mysteries the Standard Model can’t explain” 

    Symmetry Mag

    10/18/18 [Just found this. Sorry, Oscar]
    Oscar Miyamoto Gomez

    Standard Model of Particle Physics from Symmetry Magazine.

    The Standard Model is a thing of beauty. It is the most rigorous theory of particle physics, incredibly precise and accurate in its predictions. It mathematically lays out the 17 building blocks of nature: six quarks, six leptons, four force-carrier particles, and the Higgs boson.

    CERN CMS Higgs Event May 27, 2012.


    CERN ATLAS Higgs Event
    June 12, 2012.

    These are ruled by the electromagnetic, weak and strong forces.

    “As for the question ‘What are we?’ the Standard Model has the answer,” says Saúl Ramos, a researcher at the National Autonomous University of Mexico (UNAM). “It tells us that every object in the universe is not independent, and that every particle is there for a reason.”

    For the past 50 years such a system has allowed scientists to incorporate particle physics into a single equation that explains most of what we can see in the world around us.

    Despite its great predictive power, however, the Standard Model fails to answer five crucial questions, which is why particle physicists know their work is far from done.

    2
    llustration by Sandbox Studio, Chicago with Ana Kova.

    1. Why do neutrinos have mass?

    Three of the Standard Model’s particles are different types of neutrinos. The Standard Model predicts that, like photons, neutrinos should have no mass.

    However, scientists have found that the three neutrinos oscillate, or transform into one another, as they move. This feat is only possible because neutrinos are not massless after all.

    “If we use the theories that we have today, we get the wrong answer,” says André de Gouvêa, a professor at Northwestern University.

    The Standard Model got neutrinos wrong, but it remains to be seen just how wrong. After all, the masses neutrinos have are quite small.

    Is that all the Standard Model missed, or is there more that we don’t know about neutrinos? Some experimental results have suggested, for example, that there might be a fourth type of neutrino called a sterile neutrino that we have yet to discover.

    3
    Illustration by Sandbox Studio, Chicago with Ana Kova.

    2. What is dark matter?

    Scientists realized they were missing something when they noticed that galaxies were spinning much faster than they should be, based on the gravitational pull of their visible matter. They were spinning so fast that they should have torn themselves apart. Something we can’t see, which scientists have dubbed “dark matter,” must be giving additional mass—and hence gravitional pull—to these galaxies.

    Dark matter is thought to make up 27 percent of the contents of the universe. But it is not included in the Standard Model.

    Scientists are looking for ways to study this mysterious matter and identify its building blocks. If scientists could show that dark matter interacts in some way with normal matter, “we still would need a new model, but it would mean that new model and the Standard Model are connected,” says Andrea Albert, a researcher at the US Department of Energy’s SLAC National Laboratory who studies dark matter, among other things, at the High-Altitude Water Čerenkov Observatory in Mexico.

    HAWC High Altitude Čerenkov Experiment, a
    US Mexico Europe collaboration located on the flanks of the Sierra Negra volcano in the Mexican state of Puebla at an altitude of 4100 meters(13,500ft), at WikiMiniAtlas 18°59′41″N 97°18′30.6″W. searches for cosmic rays.

    “That would be a huge game changer.”

    4
    Illustration by Sandbox Studio, Chicago with Ana Kova.

    3. Why is there so much matter in the universe?

    Whenever a particle of matter comes into being—for example, in a particle collision in the Large Hadron Collider or in the decay of another particle—normally its antimatter counterpart comes along for the ride. When equal matter and antimatter particles meet, they annihilate one another.

    Scientists suppose that when the universe was formed in the Big Bang, matter and antimatter should have been produced in equal parts. However, some mechanism kept the matter and antimatter from their usual pattern of total destruction, and the universe around us is dominated by matter.

    The Standard Model cannot explain the imbalance. Many different experiments are studying matter and antimatter in search of clues as to what tipped the scales.

    5
    Illustration by Sandbox Studio, Chicago with Ana Kova.

    4. Why is the expansion of the universe accelerating?

    Before scientists were able to measure the expansion of our universe, they guessed that it had started out quickly after the Big Bang and then, over time, had begun to slow. So it came as a shock that, not only was the universe’s expansion not slowing down—it was actually speeding up.

    The latest measurements by the Hubble Space Telescope and the European Space Agency observatory Gaia indicate that galaxies are moving away from us at 45 miles per second. That speed multiplies for each additional megaparsec, a distance of 3.2 million light years, relative to our position.

    This rate is believed to come from an unexplained property of space-time called dark energy, which is pushing the universe apart. It is thought to make up around 68 percent of the energy in the universe. “That is something very fundamental that nobody could have anticipated just by looking at the Standard Model,” de Gouvêa says.

    6
    Illustration by Sandbox Studio, Chicago with Ana Kova.

    5. Is there a particle associated with the force of gravity?

    The Standard Model was not designed to explain gravity. This fourth and weakest force of nature does not seem to have any impact on the subatomic interactions the Standard Model explains.

    But theoretical physicists think a subatomic particle called a graviton might transmit gravity the same way particles called photons carry the electromagnetic force.

    “After the existence of gravitational waves was confirmed by LIGO, we now ask: What is the smallest gravitational wave possible? This is pretty much like asking what a graviton is,” says Alberto Güijosa, a professor at the Institute of Nuclear Sciences at UNAM.

    More to explore

    These five mysteries are the big questions of physics in the 21st century, Ramos says. Yet, there are even more fundamental enigmas, he says: What is the source of space-time geometry? Where do particles get their spin? Why is the strong force so strong while the weak force is so weak?

    There’s much left to explore, Güijosa says. “Even if we end up with a final and perfect theory of everything in our hands, we would still perform experiments in different situations in order to push its limits.”

    “It is a very classic example of the scientific method in action,” Albert says. “With each answer come more questions; nothing is ever done.”

    See the full article here .


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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 6:49 pm on September 23, 2020 Permalink | Reply
    Tags: "New Molecules from GOTHAM", , An Attack from All Angles, , , , , , Hiding in Slow Motion, The Search for New Chemistry   

    From AAS NOVA: “New Molecules from GOTHAM” 

    AASNOVA

    From AAS NOVA

    23 September 2020
    Susanna Kohler

    1
    Infrared view of the Taurus Molecular Cloud complex captured with Herschel. [ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech).]

    ESA/Herschel spacecraft active from 2009 to 2013.

    What as-yet unidentified molecules lurk in the dark clouds of our nearby universe? Answering this requires observation, experiment, and theory — and GOTHAM is on the case.

    The Search for New Chemistry

    2
    Another view of the Taurus Molecular Cloud, captured here in millimeter wavelengths by the APEX telescope. [ESO.]

    ESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    In the census of the molecular makeup of our universe, the interstellar medium (ISM) is the best target for diversity: we’ve spotted just over 200 different molecules in our galaxy’s ISM. We expect that there are many more out there, however — and identifying where these different molecules are found will help us to understand when and how they form.

    To this end, a team of scientists is undertaking the GOTHAM project [GBT Observations of TMC-1: Hunting Aromatic Molecules]: a radio search of a cold, dark cloud located 450 light-years away called the Taurus Molecular Cloud 1 (TMC-1). This chilly cloud has not yet collapsed to form a star, providing us with an opportunity to identify new molecules that are able to form in a cold, pre-stellar environment.

    Hiding in Slow Motion

    Green Bank Radio Telescope, West Virginia, USA, now the center piece of the GBO, Green Bank Observatory, being cut loose by the NSF, supported by Breakthrough Listen.

    But the hunt for molecules in a cold, dark cloud is challenging! We generally identify molecules by searching for their signature transition lines in ISM spectra. But in cold clouds, molecules aren’t moving much, which makes their spectral lines very narrow. This means that we need extremely high-spectral-resolution telescopes to be able to identify them. Fortunately, GOTHAM leverages the 100-meter Green Bank Telescope (GBT), which is up to the task!

    In a new article led by Brett McGuire (MIT, NRAO, and Center for Astrophysics | Harvard & Smithsonian), a team of scientists details the GOTHAM project and its early science results. This is just one of six new articles that describe the first molecular detections by GOTHAM.

    An Attack from All Angles

    How does a new molecular detection work? As an example, we can look at GOTHAM’s discovery of propargyl cyanide (HCCCH2CN) in TMC-1.

    First, due to the GBT’s high spectral resolution, the team needed to produce new, fine-detail guides for the forest of spectral lines expected from propargyl cyanide. This required new laboratory measurements of the molecule.

    4
    Individual line detections of propargyl cyanide in the GOTHAM data. [McGuire et al. 2020.]

    Next, the team had to search for these lines in the GBT data. Propargyl cyanide has 3,700 transitions that fall within GOTHAM’s observing range, all contributing to the total flux seen for this molecule. Teasing out these signatures requires complex data analysis.

    Finally, after achieving a significant detection of the molecule, the team had to do a sanity check. They conducted simulations of TMC-1 using astrochemical codes and included different channels that could form and destroy propargyl cyanide. They then checked that the abundances they measured for this molecule matched expectations from the simulations.

    More Discoveries Ahead

    This multi-faceted process has already led to a number of new detections in addition to propargyl cyanide. The detections are announced across a set of six articles — including an additional ApJ Letters publication, in which Ci Xue (University of Virginia, Charlottesville) and collaborators detail the first astronomical detection of isocyanodiacetylene (HC4NC) and the implications for how this molecule and others like it form in the ISM.

    What’s more, all of these new results still only make up 30% of the eventual data that will be collected for the GOTHAM project. There’s plenty more to look forward to in the future as we continue to expand our understanding of the chemistry of the universe around us.

    Citation

    “Early Science from GOTHAM: Project Overview, Methods, and the Detection of Interstellar Propargyl Cyanide (HCCCH2CN) in TMC-1,” Brett A. McGuire et al 2020 ApJL 900 L10.
    https://iopscience.iop.org/article/10.3847/2041-8213/aba632

    “Detection of Interstellar HC4NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions,” Ci Xue et al 2020 ApJL 900 L9 [above].

    See the full article here .


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    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 6:18 pm on September 23, 2020 Permalink | Reply
    Tags: "New photodetector is a shining light", , , RMIT University, The RMIT prototype can interpret light ranging from deep ultraviolet to near infrared wavelengths making it sensitive to a broader spectrum than a human eye. And it is less than a nanometre thick., Ultra-thin prototype can see the full spectrum.   

    From RMIT University AU via COSMOS: “New photodetector is a shining light” 

    RMIT AU

    From RMIT University AU

    via

    Cosmos Magazine bloc

    COSMOS

    23 September 2020

    Ultra-thin prototype can see the full spectrum.

    1
    An artist’s impression of RMIT University’s prototype photodetector. Credit: Ella Marushchenko.

    Australian engineers appear to have raised the bar for photodetector technology, developing a device that is incredibly thin but able to see all shades of light.

    Writing in the journal Advanced Materials, researchers from RMIT University, led by Vaishnavi Krishnamurthi, suggest their successful prototype provides new opportunities to integrate electrical and optical components on the same chip.

    Photodetectors, or photosensors, work by converting information carried by light into an electrical signal, and are used in everything from gaming consoles to fibre optic communication.

    However, they currently are unable to sense more than one colour in the one device, Krishnamurthi says, which means they have remained bigger and slower than other technologies, such as the silicon chip, with which they integrate.

    The RMIT prototype can interpret light ranging from deep ultraviolet to near infrared wavelengths, making it sensitive to a broader spectrum than a human eye. And it is less than a nanometre thick.

    Success came from taking a completely different approach.

    Current photodetector technology relies on a stacked structure of three to four layers, but the RMIT team worked out how to use a nanothin layer –a single atom thick – on a chip.

    The material used, tin monosulfide, also is low-cost and naturally abundant, making it attractive for electronics and optoelectronics, says co-author and chief investigator Sumeet Walia.

    “The material allows the device to be extremely sensitive in low-lighting conditions, making it suitable for low-light photography across a wide light spectrum,” he says.

    A major challenge was ensuring electronic and optical properties didn’t deteriorate when the photodetector was shrunk – a technological bottleneck that, the researchers say, had previously prevented miniaturisation of light detection technologies.

    Walia says the team is now looking at industry applications for the photodetector, which can be integrated with existing technologies such as CMOS chips.

    “With further development, we could be looking at applications including more effective motion detection in security cameras at night and faster, more efficient data storage,” he says.

    See the full article here .


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    Success came from taking a completely different approach.

    Current photodetector technology relies on a stacked structure of three to four layers, but the RMIT team worked out how to use a nanothin layer –a single atom thick – on a chip.

    The material used, tin monosulfide, also is low-cost and naturally abundant, making it attractive for electronics and optoelectronics, says co-author and chief investigator Sumeet Walia.

    “The material allows the device to be extremely sensitive in low-lighting conditions, making it suitable for low-light photography across a wide light spectrum,” he says.

    A major challenge was ensuring electronic and optical properties didn’t deteriorate when the photodetector was shrunk – a technological bottleneck that, the researchers say, had previously prevented miniaturisation of light detection technologies.

    Walia says the team is now looking at industry applications for the photodetector, which can be integrated with existing technologies such as CMOS chips.

    “With further development, we could be looking at applications including more effective motion detection in security cameras at night and faster, more efficient data storage,” he says.

     
  • richardmitnick 5:45 pm on September 23, 2020 Permalink | Reply
    Tags: "UCLA scientists create world’s smallest ‘refrigerator’", An additional distinguishing feature of the team’s nanoscale “refrigerator” is that it can respond almost instantly., , At larger scales the same technology is used to cool computers and other electronic devices., Indium nanoparticles which the team used as thermometers., , , The scientific instruments on NASA’s Voyager spacecraft have been powered for 40 years by electricity from thermoelectric devices wrapped around heat-producing plutonium., Thermoelectric coolers that are only 100 nanometers thick., UC Los Angeles, When heat is applied one side becomes hot and the other remains cool; that temperature difference can be used to generate electricity.   

    From UC Los Angeles: “UCLA scientists create world’s smallest ‘refrigerator’” 

    UCLA bloc

    From UC Los Angeles

    September 22, 2020

    Lisa Garibay
    310-825-1040
    lgaribay@ucla.edu

    1
    Dewdrop forms on thermoelectric cooler. A team led by UCLA physics professor Chris Regan has succeeded in creating thermoelectric coolers that are only 100 nanometers thick — roughly one ten-millionth of a meter — and have developed an innovative new technique for measuring their cooling performance. Credit: UCLA/Regan Group.

    2
    This electron microscope image shows the cooler’s two semiconductors — one flake of bismuth telluride and one of antimony-bismuth telluride — overlapping at the dark area in the middle, which is where most of the cooling occurs. The small “dots” are indium nanoparticles, which the team used as thermometers. UCLA/Regan Group

    How do you keep the world’s tiniest soda cold? UCLA scientists may have the answer.

    A team led by UCLA physics professor Chris Regan has succeeded in creating thermoelectric coolers that are only 100 nanometers thick — roughly one ten-millionth of a meter — and have developed an innovative new technique for measuring their cooling performance.

    “We have made the world’s smallest refrigerator,” said Regan, the lead author of a paper on the research published recently in the journal ACS Nano.

    To be clear, these miniscule devices aren’t refrigerators in the everyday sense — there are no doors or crisper drawers. But at larger scales, the same technology is used to cool computers and other electronic devices, to regulate temperature in fiber-optic networks, and to reduce image “noise” in high-end telescopes and digital cameras.

    What are thermoelectric devices and how do they work?

    Made by sandwiching two different semiconductors between metalized plates, these devices work in two ways. When heat is applied, one side becomes hot and the other remains cool; that temperature difference can be used to generate electricity. The scientific instruments on NASA’s Voyager spacecraft, for instance, have been powered for 40 years by electricity from thermoelectric devices wrapped around heat-producing plutonium. In the future, similar devices might be used to help capture heat from your car’s exhaust to power its air conditioner.

    3
    A standard thermoelectric device, which is made of two semiconductor materials sandwiched between metalized plates. Wikimedia Commons.

    But that process can also be run in reverse. When an electrical current is applied to the device, one side becomes hot and the other cold, enabling it to serve as a cooler or refrigerator. This technology scaled up might one day replace the vapor-compression system in your fridge and keep your real-life soda frosty.

    What the UCLA team did

    To create their thermoelectric coolers, Regan’s team, which included six UCLA undergraduates, used two standard semiconductor materials: bismuth telluride and antimony-bismuth telluride. They attached regular Scotch tape to hunks of the conventional bulk materials, peeled it off and then harvested thin, single-cystal flakes from the material still stuck to the tape. From these flakes, they made functional devices that are only 100 nanometers thick and have a total active volume of about 1 cubic micrometer, invisible to the naked eye.

    To put this tiny volume in perspective: Your fingernails grow by thousands of cubic micrometers every second. If your cuticles were manufacturing these tiny coolers instead of fingernails, each finger would be churning out more than 5,000 devices per second.

    “We beat the record for the world’s smallest thermoelectric cooler by a factor of more than ten thousand,” said Xin Yi Ling, one of the paper’s authors and a former undergraduate student in Regan’s research group.

    While thermoelectric devices have been used in niche applications due to advantages such as their small size, their lack of moving parts and their reliability, their low efficiency compared with conventional compression-based systems has prevented widespread adoption of the technology. Simply put, at larger scales, thermoelectric devices don’t generate enough electricity, or stay cold enough — yet.

    But by focusing on nanostructures — devices with at least one dimension in the range of 1 to 100 nanometers — Regan and his team hope to discover new ways of synthesizing better-performing bulk materials. The sought-after properties for materials in high-performance thermoelectric coolers are good electrical conductivity and poor thermal conductivity, but these properties are almost always mutually exclusive. However, a winning combination might be found in nearly two-dimensional structures like those Regan’s team has created.

    An additional distinguishing feature of the team’s nanoscale “refrigerator” is that it can respond almost instantly.

    “Its small size makes it millions of times faster than a fridge that has a volume of a millimeter cubed, and that would be already be millions of times faster than the fridge you have in your kitchen,” Regan said.

    “Once we understand how thermoelectric coolers work at the atomic and near-atomic level,” he said, “we can scale up to the macroscale, where the big payoff is.”

    Measuring how cold the devices become

    Measuring temperature in such tiny devices is a challenge. Optical thermometers have poor resolution at such small scales, while scanning probe techniques require specialized, expensive equipment. Both approaches require painstaking calibrations.

    In 2015, Regan’s research group developed a thermometry technique called PEET, or plasmon energy expansion thermometry, which uses a transmission electron microscope to determine temperatures at the nanoscale by measuring changes in density.

    To measure the temperature of their thermoelectric coolers, the researchers deposited nanoparticles made of the element indium on each one and selected one specific particle to be their thermometer. As the team varied the amount of power applied to the coolers, the devices heated and cooled, and the indium correspondingly expanded and contracted. By measuring the indium’s density, the researchers were able to determine the precise temperature of the nanoparticle and thus the cooler.

    “PEET has the spatial resolution to map thermal gradients at the few-nanometer scale — an almost unexplored regime for nanostructured thermoelectric materials,” said Regan, who is a member of the California NanoSystems Institute at UCLA.

    To supplement the PEET measurements, the researchers invented a technique called condensation thermometry. The basic idea is simple: When normal air cools to a certain temperature — the dew point — water vapor in the air condenses into liquid droplets, either dew or rain. The team exploited this effect by powering their device while watching it with an optical microscope. When the device reached the dew point, tiny dewdrops instantly formed on its surface.

    Regan praised the work of his student researchers in helping to develop and measure the performance the nanoscale devices.

    “Connecting advanced materials science and electron microscopy to physics in everyday areas, like refrigeration and dew formation, helps students get traction on the problems very quickly,” Regan said. “Watching them learn and innovate gives me a lot of hope for the future of thermoelectrics.”

    See the full article here .

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    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 4:22 pm on September 23, 2020 Permalink | Reply
    Tags: "Study investigates the nature of X-ray binary IGR J18214-1318", , , , ,   

    From phys.org: “Study investigates the nature of X-ray binary IGR J18214-1318” 


    From phys.org

    September 22, 2020
    Tomasz Nowakowski

    1
    Swift’s XRT and BAT broadband spectrum of IGR J18214-1318. Top panel: data and best-fit model tbabs*pcfabs*(nthComp). Bottom panel: residuals in units of standard deviations. Credit: Cusumano et al., 2020.

    Using various space observatories, Italian astronomers have investigated an X-ray binary source known as IGR J18214-1318. Results of the study, detailed in a paper published by MNRAS provide important information about the properties of this system, shedding more light into its nature.

    X-ray binaries consist of a normal star or a white dwarf transferring mass onto a compact neutron star or a black hole. Based on the mass of the companion star, astronomers divide them into low-mass X-ray binaries (LMXBs) and high-mass X-ray binaries (HMXBs).

    IGR J18214-1318 is an HMXB detected with the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellite in 2006.

    ESA/Integral.

    The object is associated to USNO-B1.0 0766-0475700—most likely a star of spectral type O9I.

    In order to get more insights into the nature of IGR J18214-1318, a team of astronomers led by Giancarlo Cusumano of the Institute of Space Astrophysics and Cosmic Physics in Palermo, Italy, has analyzed a dataset covering 13 years of observations of this source with NASA’s Swift spacecraft.

    NASA Neil Gehrels Swift Observatory.

    The study was complemented by data from ESA’s XMM-Newton and NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) spacecraft.

    ESA/XMM Newton X-ray telescope.

    NASA/DTU/ASI NuSTAR X-ray telescope.

    “In this work we present a temporal and spectral analysis of IGR J18214-1318, a source discovered by INTEGRAL on the galactic plane. (…) We exploited archival data based on Swift, XMM-Newton, and NuSTAR data available on IGR J18214-1318 for an updated study of the spectral and timing properties of this source,” the astronomers wrote in the paper.

    The results indicate that IGR J18214-1318 has an orbital period of approximately 5.42 days. It was calculated that the mass of the system’s neutron star is around 1.4 solar masses, while the companion star, with a radius of about 22 solar radii, turned out to be some 30 times more massive than our sun.

    Based on the results, the researchers estimated that the two components of IGR J18214-1318 are separated by about 41 solar radii, which is a relatively close distance, taking into account the size of the companion star. The astronomers concluded that such tight orbital separation and spectral type of the companion (O9) suggest that IGR J18214-1318 is a wind-accreting source with eccentricity lower than 0.17.

    “Such a tight orbital separation is common among wind-fed neutron stars accreting from an O type companion star,” the authors of the paper noted.

    Furthermore, results from Swift show that the 1–10 keV X-ray spectrum of IGR J18214-1318 is variable. This is because of the changing of local conditions on the neutral absorption and of the accretion rate. When it comes to the hard X-ray spectrum (above 15 keV), it appears to be generally dominated by the exponential tail of the Comptonized component, and depends only on the electrons temperature and the instantaneous mass accretion rate.

    See the full article here .

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    About Science X in 100 words
    Science X™ is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004 (Physorg.com), Science X’s readership has grown steadily to include 5 million scientists, researchers, and engineers every month. Science X publishes approximately 200 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Science X community members enjoy access to many personalized features such as social networking, a personal home page set-up, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.
    Mission 12 reasons for reading daily news on Science X Organization Key editors and writersinclude 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 3:59 pm on September 23, 2020 Permalink | Reply
    Tags: "Controlling ultrastrong light-matter coupling at room temperature", , , , Ultrastrong coupling between light and matter at room temperature.   

    From Chalmers University of Technology SE: “Controlling ultrastrong light-matter coupling at room temperature” 

    From Chalmers University of Technology SE

    Sep 23, 2020
    Johanna Wilde
    Press officer
    +46-31-772 2029
    johanna.wilde@chalmers.se

    1
    Photographer: Illustration: Denis Baranov, Chalmers University of Technology

    Physicists at Chalmers University of Technology in Sweden, together with colleagues in Russia and Poland, have managed to achieve ultrastrong coupling between light and matter at room temperature. The discovery is of importance for fundamental research and might pave the way for advances within, for example, light sources, nanomachinery, and quantum technology.

    A set of two coupled oscillators is one of the most fundamental and abundant systems in physics. It is a very general toy model that describes a plethora of systems ranging from guitar strings, acoustic resonators, and the physics of children’s swings, to molecules and chemical reactions, from gravitationally bound systems to quantum cavity electrodynamics.

    The degree of coupling between the two oscillators is an important parameter that mostly determines the behaviour of the coupled system. However, the question is rarely asked about the upper limit by which two pendula can couple to each other – and what consequences such coupling can have.

    The newly presented results, published in Nature Communications, offer a glimpse into the domain of the so called ultrastrong coupling, wherein the coupling strength becomes comparable to the resonant frequency of the oscillators. The coupling in this work is realised through interaction between light and electrons in a tiny system consisting of two gold mirrors separated by a small distance and plasmonic gold nanorods. On a surface that is a hundred times smaller than the end of a human hair, the researchers have shown that it is possible to create controllable ultrastrong interaction between light and matter at ambient conditions – that is, at room temperature and atmospheric pressure.

    ”We are not the first ones to realise ultrastrong coupling. But generally, strong magnetic fields, high vacuum and extremely low temperatures are required to achieve such a degree of coupling. When you can perform it in an ordinary lab, it enables more researchers to work in this field and it provides valuable knowledge in the borderland between nanotechnology and quantum optics,” says Denis Baranov, a researcher at Chalmers University of Technology and the first author of the scientific paper.

    A unique duet where light and matter intermix into a common object

    To understand the system the authors have realised, one can imagine a resonator, in this case represented by two gold mirrors separated by a few hundred nanometers, as a single tone in music. The nanorods fabricated between the mirrors affect how light moves between the mirrors and change their resonance frequency. Instead of just sounding like a single tone, in the coupled system the tone splits into two: a lower pitch, and a higher pitch.

    The energy separation between the two new pitches represents the strength of interaction. Specifically, in the ultrastrong coupling case, the strength of interaction is so large that it becomes comparable to the frequency of the original resonator. This leads to a unique duet, where light and matter intermix into a common object, forming quasi-particles called polaritons. The hybrid character of polaritons provides a set of intriguing optical and electronic properties.

    The number of gold nanorods sandwiched between the mirrors controls how strong the interaction is. But at the same time, it controls the so-called zero-point energy of the system. By increasing or decreasing the number of rods, it is possible to supply or remove energy from the ground state of the system and thereby increase or decrease the energy stored in the resonator box.

    The discovery allows researchers to play with the laws of nature

    What makes this work particularly interesting is that the authors managed to indirectly measure how the number of nanorods changes the vacuum energy by “listening” to the tones of the coupled system (that is, looking at the light transmission spectra through the mirrors with the nanorods) and performing simple mathematics. The resulting values turned out to be comparable to the thermal energy, which may lead to observable phenomena in the future.

    “A concept for creating controllable ultrastrong coupling at room temperature in relatively simple systems can offer a testbed for fundamental physics. The fact that this ultrastrong coupling “costs” energy could lead to observable effects, for example it could modify the reactivity of chemicals or tailor van der Waals interactions. Ultrastrong coupling enables a variety of intriguing physical phenomena,” says Timur Shegai, Associate Professor at Chalmers and the last author of the scientific article.

    In other words, this discovery allows researchers to play with the laws of nature and to test the limits of coupling.

    “As the topic is quite fundamental, potential applications may range. Our system allows for reaching even stronger levels of coupling, something known as deep strong coupling. We are still not entirely sure what is the limit of coupling in our system, but it is clearly much higher than we see now. Importantly, the platform that allows studying ultrastrong coupling is now accessible at room temperature,” says Timur Shegai.

    For more information, please contact:

    Denis Baranov, Post Doc
    Department of Physics
    Chalmers University of Technology SE
    +46 31 772 32 48
    denisb@chalmers.se

    Timur Shegai, Associate Professor
    Department of Physics
    Chalmers University of Technology SE
    +46 31 772 31 23
    timurs@chalmers.se

    The researchers work at the Department of Physics and the Department of Microtechnology and Nanoscience at Chalmers University of Technology, at Moscow Institute of Physics and Technology and at the Faculty of Physics, University of Warsaw.

    The nanofabrication was performed at Chalmers. The interactions between light and matter were observed by using infrared microscopy.

    The research at Chalmers was funded by the Swedish Research Council.

    See the full article here .

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    Please help promote STEM in your local schools.

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    Chalmers University of Technology (Swedish: Chalmers tekniska högskola, often shortened to Chalmers) is a Swedish university located in Gothenburg that focuses on research and education in technology, natural science, architecture, maritime and other management areas

    The University was founded in 1829 following a donation by William Chalmers, a director of the Swedish East India Company. He donated part of his fortune for the establishment of an “industrial school”. Chalmers was run as a private institution until 1937, when the institute became a state-owned university. In 1994, the school was incorporated as an aktiebolag under the control of the Swedish Government, the faculty and the Student Union. Chalmers is one of only three universities in Sweden which are named after a person, the other two being Karolinska Institutet and Linnaeus University.

     
  • richardmitnick 3:31 pm on September 23, 2020 Permalink | Reply
    Tags: "Let them eat rocks", , , Scientists are installing sensors in the ground at five different sites to monitor microbes’ activity for the next five years., The sites have been chosen because they represent different ecosystems, , UC Riverside is leading an effort that could help ensure food security and improve the worst effects of climate change — by studying rock-eating bacteria and fungi.   

    From UC Riverside: “Let them eat rocks” 

    UC Riverside bloc

    From UC Riverside

    September 23, 2020

    Jules L Bernstein
    Senior Public Information Officer
    jules.bernstein@ucr.edu
    (951) 827-4580

    1
    Microscopy image of Tympanidaceae, a fungus found at a research sample site. (Danny Newman and Mia Maltz/UCR)

    UC Riverside is leading an effort that could help ensure food security and improve the worst effects of climate change — by studying rock-eating bacteria and fungi.

    These microbes break apart chemical bonds in deep underground layers of rocks, then die and release nutrients such as nitrogen and phosphorus into the soil. Aside from fertilizer, this is the main way soil obtains these nutrients, and agriculture is dependent on the process.

    “Despite how critical they are for food production, our general knowledge of microbes in soils is so lacking,” said Emma Aronson, associate professor of microbiology and plant pathology.

    A new $4.2 million National Science Foundation grant aims to close the gap in scientists’ understanding. It will enable scientists to install sensors in the ground at five different sites and monitor the microbes’ activity for the next five years.

    The sensors will measure, among other things, carbon dioxide concentration at these sites throughout the five years of the study. “We’ll be able to watch the microbes breathing deep in the soil,” Aronson said.

    2
    Bioinformatics specialist Keshav Arogyaswamy digging toward bedrock to sample deep soil microbes in California’s southern Sierra Nevada. Credit Emma Aronson/UCR.

    The sites have been chosen because they represent different ecosystems, including a location in Idaho, the Luquillo Experimental Forest in Puerto Rico, the Great Smoky Mountains in South Carolina, the Santa Catalina mountains in Arizona, and the southern Sierra Nevada in California.

    Aronson, principal investigator of the project, said her team’s preliminary studies revealed bacterial behavior they could not explain. They found greater changes in the bacteria the deeper they looked in the soils, but only in half of the locations they sampled. With the other half, the bacteria did not change with depth.

    “We want to understand why that is,” Aronson said. “How much is this driven by rock types at the different sites? What role does vegetation play? Why do they live where they do? This grant will help us answer questions like these that will then allow scientists to test for more applied uses.”

    One application of the research could include a tool to help trap carbon in the ground. Researchers may be able to identify some deep soil bacteria that are better at extracting nutrients from rocks than others. Those bacteria would allow plants to become larger and, if they have extra nutrients, take up more carbon that would otherwise end up in the atmosphere, trapping heat.

    Bacteria that encourage plant growth also offer the potential for increased agricultural yields, and more food, which is critical given the potential for decreased crop production as the climate changes.

    This project brings together a coalition of scientists to examine the Earth’s active outer layer known as the critical zone, which extends from the top of the tallest tree down to the microbes in the bedrock. Partnering institutions include UC Berkeley and UC Merced, as well as the University of Arizona, Idaho State University, Kansas University, and the University of New Hampshire.

    A chief benefit of the project is its interdisciplinary nature, allowing collaboration between microbiologists, ecologists, geoscientists, soil, and rock scientists.

    “We are all joining to do work that we can only do together,” Aronson said.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Riverside Campus

    The University of California, Riverside is one of 10 universities within the prestigious University of California system, and the only UC located in Inland Southern California.

    Widely recognized as one of the most ethnically diverse research universities in the nation, UCR’s current enrollment is more than 21,000 students, with a goal of 25,000 students by 2020. The campus is in the midst of a tremendous growth spurt with new and remodeled facilities coming on-line on a regular basis.

    We are located approximately 50 miles east of downtown Los Angeles. UCR is also within easy driving distance of dozens of major cultural and recreational sites, as well as desert, mountain and coastal destinations.

     
  • richardmitnick 3:13 pm on September 23, 2020 Permalink | Reply
    Tags: "Could Life Exist Deep Underground on Mars?", , FIT-Florida Institute of Technology, The absence of surface water doesn’t preclude the potential for life elsewhere on a rocky object.   

    From Harvard-Smithsonian Center for Astrophysics: “Could Life Exist Deep Underground on Mars?” 

    Harvard Smithsonian Center for Astrophysics


    From Harvard-Smithsonian Center for Astrophysics

    September 23, 2020

    Amy Oliver
    Public Affairs
    Center for Astrophysics | Harvard & Smithsonian
    Fred Lawrence Whipple Observatory
    520-879-4406
    amy.oliver@cfa.harvard.edu

    1

    Recent science missions and results are bringing the search for life closer to home, and scientists at the Center for Astrophysics | Harvard & Smithsonian (CfA) and the Florida Institute of Technology (FIT) may have figured out how to determine whether life is—or was—lurking deep beneath the surface of Mars, the Moon, and other rocky objects in the universe.

    While the search for life typically focuses on water found on the surface and in the atmosphere of objects, Dr. Avi Loeb, Frank B. Baird Jr. Professor of Science at Harvard and CfA astronomer, and Dr. Manasvi Lingam, assistant professor of astrobiology at FIT and CfA astronomer, suggest that the absence of surface water doesn’t preclude the potential for life elsewhere on a rocky object, like deep in the subsurface biosphere.

    “We examined whether conditions amenable to life could exist deep underneath the surface of rocky objects like the Moon or Mars at some point in their histories and how scientists might go about searching for traces of past subsurface life on these objects,” said Lingam, the lead author on the research. “We know that these searches will be technically challenging, but not impossible.”

    One challenge for researchers was determining the potential for the existence of water where there appears to be none. “Surface water requires an atmosphere to maintain a finite pressure, without which liquid water cannot exist. However, when one moves to deeper regions, the upper layers exert pressure and thus permit the existence of liquid water in principle,” said Lingam. “For instance, Mars does not currently have any longstanding bodies of water on its surface, but it is known to have subsurface lakes.”

    The research analyzes the “thickness” of the subsurface region—where water and life might exist in principle—of the nearby rocky objects, and whether the high pressures therein could rule out life altogether. According to Loeb, the answer is probably not. “Both the Moon and Mars lack an atmosphere that would allow liquid water to exist on their surfaces, but the warmer and pressurized regions under the surface could allow the chemistry of life in liquid water.”

    The research also arrived at a limit on the amount of biological material that might exist in deep subsurface environments, and the answer, although small, is surprising. “We found that the biological material limit might be a few percent that of Earth’s subsurface biosphere, and a thousand times smaller than Earth’s global biomass,” said Loeb, adding that cryophiles—organisms that thrive in extremely cold environments—could not only potentially survive, but also multiply, on seemingly lifeless rocky bodies. “Extremophilic organisms are capable of growth and reproduction at low subzero temperatures. They are found in places that are permanently cold on Earth, such as the polar regions and the deep sea, and might also exist on the Moon or Mars.”

    In terms of searching for life subsurface on the Moon and Mars, the researchers note it won’t be easy, requiring search criteria and machinery not yet in use on either neighboring body. “There are many criteria involved in determining the most optimal locations to hunt for signs of life,” said Lingam. “Some that we have taken into account for subsurface searches include drilling near to the equator where the subsurface biosphere is situated closer to the surface, and seeking geological hotspots with higher temperatures.” Loeb added that in terms of machinery, “We need to be able to drill tens of kilometers under the surface of Mars, and without geological activity exposing these deep layers, we will not be able to explore them.”

    The challenges, however, don’t mean that finding life in the subsurface biosphere of a rocky body is impossible, even in the near future. “Drilling might be possible in the context of the Artemis program to establish a sustainable base on the Moon by 2024. One can imagine robots and heavy machinery that will drill deep under the lunar surface in search of life, just as we do in searching for oil on Earth,” said Loeb, adding that if future missions to Mars and the Moon do unearth subsurface life, the same principles could be applied to missions headed much farther away. “Our study extends to all objects out there and indeed implies that the habitable zone is much larger than traditionally thought, since science currently considers only life on the surface of the object.”

    The research is published in The Astrophysical Journal Letters.

    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 Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

     
  • richardmitnick 2:48 pm on September 23, 2020 Permalink | Reply
    Tags: "Big Astronomy Planetarium Program and Online Activities Go Live!", , , , , CTIO is home to 35 telescopes located at an altitude of 2200 meters (7200 feet) atop Cerro Tololo in northern Chile., Gemini South in Chile atop Cerro Pachón began viewing the sky in 2002.,   

    From NOIRLab: “Big Astronomy Planetarium Program and Online Activities Go Live!” 

    NOIRLab composite

    From NOIRLab

    22 September 2020
    Peter Michaud
    pmichaud@gemini.edu
    NewsTeam Manager, NSF’s NOIRLab
    Hilo, HI, USA
    Tel: +1 808 936 6643

    1
    Big Astronomy or Astronomia a Gran Escala is a bilingual planetarium show that extends beyond the dome using web-based and hands-on resources. In Big Astronomy, discover Chile’s grand observatories and meet the people who push the limits of technology and expand what we know about the Universe using world-class telescopes.

    Big Astronomy or Astronomia a Gran Escala shares the story of the people and places who make big astronomy and big science happen. The planetarium show transports viewers to Chile where the dark skies and dry, remote setting create ideal conditions to observe the Universe. By 2022, it is expected that most of the world’s ground-based observing infrastructure will be located in Chile, and the US and other countries are investing billions of dollars in furthering astronomy partnerships in the country. Big Astronomy introduces audiences to the wide variety of people involved in advancing astronomical discovery.

    Produced by the California Academy of Sciences, the Big Astronomy planetarium show has its world premiere on 26 September 2020. Owing to the pandemic, most planetariums around the world are closed, so the premiere will take place as an immersive 360-degree experience, viewable at noon PDT on either the Big Astronomy YouTube channel or the Academy YouTube channel. On launch day, the Big Astronomy YouTube channel will also offer additional screenings at 5 pm and 7 pm PDT as well as one in Spanish at 2 pm PDT. Beginning on 30 September 2020, viewers can enjoy Big Astronomy on YouTube every Wednesday at 11:30 am PDT until further notice.

    The NOIRLab facilities in Chile featured in this extraordinary planetarium production are the Cerro Tololo Inter-American Observatory (CTIO) and the international Gemini Observatory.. Other facilities featured are the Atacama Large Millimeter/submillimeter Array (ALMA) and Vera C. Rubin Observatory.

    CTIO is home to 35 telescopes, located at an altitude of 2,200 meters (7,200 feet) atop Cerro Tololo in northern Chile. An icon of CTIO is the Víctor M. Blanco 4-meter Telescope, outfitted with the Dark Energy Camera. In Big Astronomy, NOIRLab staff, including electronics/detector engineer Marco Bonati, assistant observer Jacqueline Seron, and astronomer Kathy Vivas, describe their work at the telescope and with the Dark Energy Camera.

    Gemini Observatory operates twin 8.1-meter optical telescopes located in Chile and Hawai‘i. Gemini South in Chile, atop Cerro Pachón, began viewing the sky in 2002. For Big Astronomy, NOIRLab staff, including electronics engineer Vanessa Montes and Science Operations Specialist Alysha Shugart, describe how observations are made with the Gemini Planet Imager (GPI).

    “Chile is one of the best places in the world for astronomy and we are privileged to have a presence in the country,” said Patrick McCarthy, Director of NOIRLab. “The Big Astronomy planetarium show captures in rich detail some of the people and the locations that make our work, and the work of other astronomical institutions, possible.”

    The show is now available for planetariums from the Big Astronomy website. Planetariums can download a copy for streaming and as 2k planetarium frames or order 4k planetarium frames with soundtracks in both English and Spanish.

    Big Astronomy doesn’t end with the planetarium show, though. The team has also developed an educator guide, a bilingual flat-screen version of the film, and a toolkit with a variety of hands-on activities to further engage learners of all ages. In addition, over the next two years, Big Astronomy will host a series of live virtual events featuring the diverse careers of real people who work at the facilities. All these pieces, including the planetarium show, will culminate in a new research-based model to inform the creation of future, more engaging, planetarium shows.

    More information

    Big Astronomy is a collaboration between Abrams Planetarium at Michigan State University, Associated Universities Inc. (AUI), Association of Universities for Research in Astronomy (AURA), Astronomical Society of the Pacific (ASP), California Academy of Sciences, Peoria Riverfront Museum, Ward Beecher Planetarium at Youngstown State University, the Atacama Large Millimeter-submillimeter Array (ALMA), Vera C. Rubin Observatory construction project, NSF’s NOIRLab facilities Cerro Tololo Inter-American Observatory (CTIO) and the international Gemini Observatory. Big Astronomy is supported by the US National Science Foundation (Award #: 1811436).

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition
    What is NSF’s NOIRLab?

    NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and the Vera C. Rubin Observatory. It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawaiʻi, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

     
  • richardmitnick 2:11 pm on September 23, 2020 Permalink | Reply
    Tags: "Berkeley Team Plays Key Role in Analysis of Particle Interactions That Produce Matter From Light", , , CERN’s ATLAS detector produced W bosons from photons which are particles of light., , , , , Photons are particles of light that carry the electromagnetic force which is the fundamental force associated with magnetism and electricity., , W bosons carry the weak force which is associated with the fusion that powers the sun and with nuclear fission that takes place in nuclear power plant reactors.   

    From Lawrence Berkeley National Lab: “Berkeley Team Plays Key Role in Analysis of Particle Interactions That Produce Matter From Light” 


    From Lawrence Berkeley National Lab

    September 23, 2020
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 520-0843

    1
    This image shows a reconstruction of a particle event at CERN’s ATLAS detector that produced W bosons from photons, which are particles of light. (Credit: ATLAS collaboration.)

    Researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) played a key role in an analysis of data from the world’s largest particle collider that found proof of rare, high-energy particle interactions in which matter was produced from light.

    Simone Pagan Griso, a Berkeley Lab physicist and Divisional Fellow who coordinated the efforts of the Berkeley Lab team, said his team found about 174 particle interactions that are consistent with the creation of pairs of heavy force-carrying particles called W bosons from the collision of two photons.

    Photons are particles of light that carry the electromagnetic force, which is the fundamental force associated with magnetism and electricity. W bosons carry the weak force, which is associated with the fusion that powers the sun, and with a nuclear reaction called nuclear fission that takes place in nuclear power plant reactors.

    From 2015 to 2018, only about one of the approximately 30 trillion proton interactions measured at the ATLAS detector at CERN’s Large Hadron Collider (LHC) would produce W boson pairs from the interaction of two photons per data-taking day, Pagan Griso said.

    CERN ATLAS Image Claudia Marcelloni.

    The LHC is designed to accelerate and collide protons, which are positively charged particles found in atomic nuclei. The acceleration of bunches of these particles to nearly the speed of light produces strong electromagnetic fields that accompany the proton bunches and act like a field of photons. So when these high-energy photon bunches pass each other very closely at the LHC, their electromagnetic fields may interact, causing what’s known as an “ultra-peripheral collision.”

    Unlike the destructive proton-proton particle collisions that are used to generate a swarm of constituent particles and lead to particle interactions that are typically studied at the LHC, these ultra-peripheral collisions are more like rocks skipping across a surface. The interacting fields produce “quasi-real” photons, which are effects that resemble genuine photons in their characteristics but are not actual particles.

    In this latest analysis, the researchers focused on those rare occasions when the quasi-real photons produced pairs of W bosons.

    “It’s around 1,000 times less likely to happen than a quark-initiated W boson pair creation,” which presented a challenge in filtering out these more common types of interactions, Pagan Griso noted.

    “We had to be able to predict how much background we expected relative to a signal, and all of the other interactions that happen nearby,” he said. “This meant a lot of modeling and simulations to understand what different phenomena will look like.” Ultimately, the W boson pairs produced from the photon-photon interactions decayed down to an electron and a muon, a particle in the same class as the electron but with a mass 200 times greater.

    Also participating in Berkeley Lab’s analysis were Aleksandra Dimitrievska, a postdoctoral researcher and Chamberlain Fellow in the Physics Division; William Patrick Mccormack, a Ph.D. student at UC Berkeley and a Berkeley Lab researcher; and Maurice Garcia-Sciveres and Juerg Beringer, who are both senior staff scientists at Berkeley Lab.

    Pagan Griso noted that there was some hint for the production of W boson pairs from photon pairs in earlier data-taking at the LHC, though it was far less conclusive than this latest analysis.

    “We wrote this measurement from A to Z,” Pagan Griso said of the Berkeley Lab team involved in the studies. “We literally were involved in the entire spectrum of this analysis.”

    He added, “With even more data expected at the LHC in the future, we can probe this even better,” and learn more about the production rate of W boson pairs from photon-photon interactions, and the strength of the self-interaction among these four bosons, which is a stringent test of the Standard Model of particle physics. The team will also try to improve its analysis techniques, he said.

    Pagan Griso and other members of the Berkeley Lab ATLAS Group started the analysis, together with international collaborators, about a year and a half ago, he said. These recent results are preliminary and the study will soon be submitted to a scientific journal.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
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