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  • richardmitnick 11:59 am on December 5, 2017 Permalink | Reply
    Tags: , , FNAL, , , , ,   

    From GIZMODO via FNAL: “Two Teams Have Simultaneously Unearthed Evidence of an Exotic New Particle” Revised to include the DZero result 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    GIZMODO bloc

    GIZMODO
    11/17/17
    Ryan F. Mandelbaum

    I can’t believe I’ve written three articles about this weird XI particle.

    1
    A tetraquark (Artwork: Fermilab)

    A few months ago, physicists observed a new subatomic particle—essentially an awkwardly-named, crazy cousin of the proton. Its mere existence has energized teams of particle physicists to dream up new ways about how matter forms, arranges itself, and exists.

    Now, a pair of new research papers using different theoretical methods have independently unearthed another, crazier particle predicted by the laws of physics. If discovered in an experiment, it would provide conclusive evidence of a whole new class of exotic particles called tetraquarks, which exist outside the established expectations of the behavior of the proton sub-parts called quarks. And this result is more than just mathematics.

    “We think this is not totally academic,” Chris Quigg, theoretical physicist from the Fermi National Accelerator Laboratory told Gizmodo. “Its discovery may well happen.”

    Bust first, some physics. Zoom all the way in and you’ll find that matter is made of atoms. Atoms, in turn, are made of protons, neutrons, and electrons. Protons and neutrons can further be divided into three quarks.

    Physicists have discovered six types of quarks, which also have names, masses, and electrical charges. Protons and neutrons are made from “up” and “down” quarks, the lightest two. But there are four rarer, heavier ones. From least to most massive, they are: “strange,” “charm,” “bottom,” and “top.” Each one has an antimatter partner—the same particle, but with the opposite electrical sign. As far as physicists have confirmed, these quarks and antiquarks can only arrange themselves in pairs or threes. They cannot exist on their own in nature.

    Scientists in the Large Hadron Collider’s LHCb collaboration recently announced spotting a new arrangement of three quarks, called the Ξcc++ or the “doubly charged, doubly charmed xi particle.”

    CERN/LHCb detector

    It had an up quark and two heavy charm quarks. But “most of these particles” with three quarks “containing two heavy quarks, charm or beauty, have not yet been found,” physicist Patrick Koppenburg from Nikhef, the Dutch National Institute for Subatomic Physics, told Gizmodo back then. “This is the first in a sense.”

    The DZero collaboration at Fermilab announced the discovery of a new particle whose quark content appears to be qualitatively different from normal.

    5
    The particle newly discovered by DZero decays into a Bs meson and pi meson. The Bs meson decays into a J/psi and a phi meson, and these in turn decay into two muons and two kaons, respectively. The dotted lines indicate promptly decaying particles.

    The study, using the full data set acquired at the Tevatron collider from 2002 to 2011 totaling 10 inverse femtobarns, identified the Bs meson through its decay into intermediate J/psi and phi mesons, which subsequently decayed into a pair of oppositely charged muons and a pair of oppositely charged K mesons respectively. Science paper in Physical Review Letters.

    With the knowledge such a particle could exist (and with the knowledge of its properties like its mass), two teams of physicists crunched the numbers in two separate ways. One team used extrapolations of the experimental data and methods they’d previously used to predict this past summer’s particle. The other used a mathematical abstraction of the real world, using approximations that take into account just how much heavier the charm, bottom, and top are than the rest to simplify the calculations.

    In both new papers published in Physical Review Letters https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.202002 and https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.202001, a stable four-quark particle with two bottom quarks, an anti-up quark, and an anti-down quark fell out of the math. Furthermore, the predicted particles’ masses were not quite the same, but similar enough to raise eyebrows.

    “As you notice, the conclusions are basically identical on a qualitative level,” Marek Karliner, author of the first study from Tel Aviv University in Israel, told Gizmodo. And while lots of tetraquark candidates have been spotted, this particle’s strange identity—including the added properties and stabilization from its two heavy bottom quarks—would offer unambiguous evidence of the particle’s existence.

    “The things we’re talking about are so weird that they couldn’t be something else,” said Quigg.

    But now it’s just a manner of finding the dang things. Quigg thought a new collider such as one proposed for China might be required.

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    Rendering of the proposed CEPC [CEPC-SppC for Circular Electron-Positron Collider and Super Proton-Proton Collider]. Photo: IHEP [China’s Institute of High Energy Physics]

    But physicists are in agreement that the sometimes-overlooked LHCb experiment has been doing some of the year’s most exciting work—Karliner thought the experiment could soon spot the particle. “My experimental colleagues are quite firm in this statement. They say that if it’s there, they will see it.” He thought the observation could come in perhaps two to three years time, though Quigg was less optimistic.

    Such unambiguous detection of the tetraquark would confirm guesses from as far back as 1964 as to how quarks arrange themselves. And the independent confirmation from different methods have made both teams confident.

    “I think we have pretty great confidence that the doubly-b tetraquark could exist,” said Quigg. “It’s just a matter of looking hard for it.”

    See the full article here .

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    “We come from the future.”

    GIZMOGO pictorial

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  • richardmitnick 12:10 pm on November 22, 2017 Permalink | Reply
    Tags: , , , , FNAL, , Intel, , ,   

    From CERN: “Fermilab joins CERN openlab, works on ‘data reduction’ project with CMS experiment” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead

    CERN

    1

    2
    Fermilab Wilson Hall

    Fermilab, the USA’s premier particle physics and accelerator laboratory, has joined CERN openlab as a research member. Researchers from the laboratory will collaborate with members of the CMS experiment and the CERN IT Department on efforts to improve technologies related to ‘physics data reduction’. This work will take place within the framework of an existing CERN openlab project with Intel on ‘big-data analytics’.

    CERN/CMS Detector

    ‘Physics data reduction’ plays a vital role in ensuring researchers are able to gain valuable insights from the vast amounts of particle-collision data produced by high-energy physics experiments, such as the CMS experiment on CERN’s Large Hadron Collider (LHC).

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    The project’s goal is to develop a new system — using industry-standard big-data tools — for filtering many petabytes of heterogeneous collision data to create manageable, but rich, datasets of a few terabytes for analysis. Using current systems, this kind of targeted data reduction can often take weeks; but the aim of the project is to be able to achieve this in a matter of hours.

    “Time is critical in analysing the ever-increasing volumes of LHC data,”says Oliver Gutsche, a Fermilab scientist working at the CMS experiment. “I am excited about the prospects CERN openlab brings to the table: systems that could enable us to perform analysis much faster and with much less effort and resources.” Gutsche and his colleagues will explore methods of ensuring efficient access to the data from the experiment. For this, they will investigate techniques based on Apache Spark, a popular open-source software platform for distributed processing of very large data sets on computer clusters built from commodity hardware. “The success of this project will have a large impact on the way analysis is conducted, allowing more optimised results to be produced in far less time,” says Matteo Cremonesi, a research associate at Fermilab. “I am really looking forward to using the new open-source tools; they will be a game changer for the overall scientific process in high-energy physics.”

    The team plans to first create a prototype of the system, capable of processing 1 PB of data with about 1000 computer cores. Based on current projections, this is about 1/20th of the scale of the final system that would be needed to handle the data produced when the High-Luminosity LHC comes online in 2026.

    Using this prototype, it should be possible to produce a benchmark (or ‘reference workload’) that can be used evaluate the optimum configuration of both hardware and software for the data-reduction system.

    “This kind of work, investigating big-data analytics techniques is vital for high-energy physics — both in terms of physics data and data from industrial control systems on the LHC,” says Maria Girone, CERN openlab CTO. “However, these investigations also potentially have far-reaching impact for a range of other disciplines. For example, this CERN openlab project with Intel is also exploring the use of these kinds of analytics techniques for healthcare data.”

    “Intel is proud of the work it has done in enabling the high-energy physics community to adopt the latest technologies for high-performance computing, data analytics, and machine learning — and reap the benefits. CERN openlab’s project on big-data analytics is one of the strategic endeavours to which Intel has been contributing,” says Stephan Gillich, Intel Deutschland’s director of technical computing for Europe, the Middle East, and Africa. “The possibility of extending the CERN openlab collaboration to include Fermilab, one of the world’s leading research centres, is further proof of the scientific relevance and success of this private-public partnership.”

    See the full article here.

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    About CERN openlab

    CERN openlab is a unique public-private partnership that accelerates the development of cutting-edge solutions for the worldwide LHC community and wider scientific research. Through CERN openlab, CERN collaborates with leading ICT companies and research institutes.

    Within this framework, CERN provides access to its complex IT infrastructure and its engineering experience, in some cases even extended to collaborating institutes worldwide. Testing in CERN’s demanding environment provides the ICT industry partners with valuable feedback on their products while allowing CERN to assess the merits of new technologies in their early stages of development for possible future use. This framework also offers a neutral ground for carrying out advanced R&D with more than one company.

    CERN openlab was created in 2001 (link is external) and is now in the phase V (2015-2017). This phase tackles ambitious challenges covering the most critical needs of IT infrastructures in domains such as data acquisition, computing platforms, data storage architectures, compute provisioning and management, networks and communication, and data analytics.

    Meet CERN in a variety of places:

    Quantum Diaries
    QuantumDiaries

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New

    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New II

    LHC

    CERN LHC Map
    CERN LHC Grand Tunnel

    CERN LHC particles

    Quantum Diaries

     
  • richardmitnick 10:44 am on November 10, 2017 Permalink | Reply
    Tags: , FNAL, , ICFA supports 250-GeV International Linear Collider and encourages its realization, ICFA-International Committee for Future Accelerators, , ,   

    From FNAL: “International Committee for Future Accelerators weighs in on International Linear Collider” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    November 9, 2017
    ICFA

    The following statement was issued today by the International Committee for Future Accelerators, a 16-member body created in 1976 to facilitate international collaboration in the construction and use of accelerators for high energy physics. Fermilab Director Nigel Lockyer is a member and past chairperson of ICFA. ICFA’s full press release is available at Interactions.org.

    Here it is so that you do not need to hunt for it.

    ICFA supports 250-GeV International Linear Collider and encourages its realization
    9 November 2017
    International Committee for Future Accelerators

    ILC schematic

    Date Issued:
    November 9th, 2017
    Source: International Committee for Future Accelerators
    Content: Press Release
    Contacts:

    Linear Collider Communicators (communicators@linearcollider.org):
    Perrine Royole-Degieux, CNRS/IN2P3, France +33 4 73 40 54 59, royole@in2p3.fr
    Rika Takahashi, KEK, Japan, +81 29 979 6292, rika.takahashi@kek.jp
    Barbara Warmbein, DESY, Germany, +49 40 8998 1847, barbara.warmbein@desy.de
    KEK Press Office, KEK, Japan, press@kek.jp

    The International Committee for Future Accelerators (ICFA) issued a statement to support the construction of the International Linear Collider (ILC) operating at 250 giga electron volts (GeV) as a so-called “Higgs factory. ICFA also stated its continuing support for the ILC and its encouragement of the collider’s timely realization as an international project led by Japanese initiative.

    The statement was issued at the 12th ICFA seminar held in Ottawa, Canada from 6 to 9 November 2017.

    “It is great to see so much congruency among all major particle physics players in the world,” said Joachim Mnich, Director of Particle Physics and Astroparticle Physics at DESY, Germany, and current chair of ICFA. “Particle physics has produced major discoveries that have attracted the attention of people around the globe like the Higgs particle. The next steps will be even more global as we further explore open fundamental questions using more powerful accelerators. The world’s scientists are coming together to chart this exciting future.”

    The full text of the ICFA statement (issued 8 November 2017):

    ICFA Statement on the ILC Operating at 250 GeV as a Higgs Boson Factory

    The discovery of a Higgs boson in 2012 at the Large Hadron Collider (LHC) at CERN is one of the most significant recent breakthroughs in science and marks a major step forward in fundamental physics. Precision studies of the Higgs boson will further deepen our understanding of the most fundamental laws of matter and its interactions.

    The International Linear Collider (ILC) operating at 250 GeV center-of-mass energy will provide excellent science from precision studies of the Higgs boson. Therefore, ICFA considers the ILC a key science project complementary to the LHC and its upgrade.

    ICFA welcomes the efforts by the Linear Collider Collaboration on cost reductions for the ILC, which indicate that up to 40% cost reduction relative to the 2013 Technical Design Report (500 GeV ILC) is possible for a 250 GeV collider.

    ICFA emphasizes the extendibility of the ILC to higher energies and notes that there is large discovery potential with important additional measurements accessible at energies beyond 250 GeV.

    ICFA thus supports the conclusions of the Linear Collider Board (LCB) in their report presented at this meeting and very strongly encourages Japan to realize the ILC in a timely fashion as a Higgs boson factory with a center-of-mass energy of 250 GeV as an international project1, led by Japanese initiative.

    1 In the LCB report the European XFEL and FAIR are mentioned as recent examples for international projects.

    Ottawa, November 2017
    About ICFA

    ICFA, the International Committee for Future Accelerators, was created to facilitate international collaboration in the construction and use of accelerators for high energy physics. The Committee has 16 members, selected primarily from the regions most deeply involved in high-energy physics.
    About the ILC

    The Linear Collider Collaboration (LCC) is an international endeavour that brings together about 2400 scientists and engineers from more than 300 universities and laboratories in 49 countries and regions. Consisting of two linear accelerators that face each other, the ILC will accelerate and collide electrons and their anti-particles, positrons. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they collide in the detectors at the centre of the machine.

    At the height of operation, bunches of electrons and positrons will collide roughly 7,000 times per second at a total collision energy of 250 GeV, creating a surge of new particles that are tracked and registered in the ILC’s detectors. Each bunch will contain 20 billion electrons or positrons concentrated into an area much smaller than that of a human hair.

    This means a very high rate of collisions. This high “luminosity”, when combined with the very precise interaction of two point-like colliding particles that annihilate each other, will allow the ILC to deliver a wealth of data to scientists that will allow the properties of particles, such as the Higgs boson, recently discovered at the Large Hadron Collider at CERN, to be measured precisely. It could also shed light on new areas of physics such as dark matter.

    The ILC had originally been designed with a collision energy on 500 GeV. The new version of the collider makes it less costly and faster to realise.

    The research and development work that is being done for accelerators and detectors around the world and to take the linear collider project to the next step is coordinated by the Linear Collider Collaboration headed by former LHC Project Manager Lyn Evans. The Linear Collider Board(LCB), representing ICFA, will provide oversight to the LCC, chaired by Tatsuya Nakada, Ecole Polytechnique Fédérale de Lausanne, Switzerland.

    http://www.linearcollider.org/ILC

    See the full article here .

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    FNAL Icon
    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 4:31 pm on November 9, 2017 Permalink | Reply
    Tags: , FNAL, , , , , Sandra Biedron,   

    From FNAL: Women in STEM- “Fermilab user Sandra Biedron awarded IEEE PAST Award” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    November 9, 2017
    No writer credit

    1
    Sandra Biedron

    The Institute of Electrical and Electronics Engineers (IEEE) Nuclear and Plasma Sciences Society recently honored long-time Fermilab user Sandra Biedron from the University of New Mexico with the Particle Accelerator Science and Technology (PAST) [terrible name for anything in science. The PAST is history science is the future] Award “for broad impact in accelerator science and technology.”

    Biedron’s research with her graduate students collaborating with Fermilab has encompassed facets of high-power electron sources for security and environmental engineering applications; intelligent controls for particle accelerators; low-level radio-frequency control; and modeling of the so-called “magnetic horns” used in the generation of muon and neutrino beams.

    A key recent research product of the Fermilab and Biedron collaboration team was an invited paper in 2016, published in IEEE’s Transactions of Nuclear Science, on neural network for modeling and control of particle accelerators. One of her students, Auralee Edelen, another Fermilab user, was first author. Additional research products from Biedron’s collaboration with Fermilab include those published in many accelerator conference proceedings, also highlighting her students as first author in many cases, illuminating her commitment not only to research but also to training next-generation scientists and engineers.

    The prestigious IEEE PAST Award goes to individuals who have made outstanding contributions to the development of particle accelerator science and technology. Previous PAST awards have gone to prominent accelerator scientists, including former Fermilab Chief Technology Officer Hasan Padamsee, current Chief Technology Officer Sergey Belomestnykh and deputy head of Fermilab’s Technical Division Anna Grassellino, and Fermilab scientist Kiyomi Seiya. See Biedron and other IEEE PAST Award recipients online. Scroll to “PAST Award” and click on “PAST Recipients.”)

    The PAST Awards will be presented at the 2018 International Particle Accelerator Conference in Vancouver, British Columbia, in May 2018.

    See the full article here .

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 12:37 pm on November 9, 2017 Permalink | Reply
    Tags: , FNAL, , , , , The art of Angela Lahs Gonzales at FNAL   

    From Symmetry: “Fermilab’s 11th employee” 

    Symmetry Mag
    Symmetry

    11/09/17
    Lauren Biron

    Fantastical designs elevate physics in works by Fermilab’s first artist.

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    Angela Gonzales, Fermilab

    Planning to start up a particle physics lab? Better hire an artist.

    That was Robert R. Wilson’s thought in the 1960s, when he began forming what would become the Department of Energy’s Fermi National Accelerator Laboratory. He wanted a space to do physics that would inspire all who set foot on the lab. He knew, even then, the importance of mingling art and science. The 11th person hired was artist Angela Lahs Gonzales, and in her three decades at the lab, she influenced the character and aesthetic of nearly every part of the site.

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    Angela Lahs Gonzales

    Gonzales, the daughter of two artists who fled with her from Nazi Germany, had worked with Wilson previously at Cornell University. At Fermilab, she found herself responsible for a multitude of artistic choices. Working closely with Wilson, she created the lab’s logo, a union of dipole and quadrupole magnets used in accelerators to guide and focus the particle beam. She chose a bold color scheme, with vibrant blues, oranges and reds that would coat Fermilab buildings. She designed covers for scientific publications and posters for lab events and lectures.

    “There was no project too small or large for Angela,” says Georgia Schwender, the curator of Fermilab’s art gallery. “She seemed to put just as much care and thought into sketches for the Annual Report as she did for a community Easter egg hunt. The whole lab was her canvas and her muse.”

    A mix of themes and styles, from history to mythology and op-art to realism, are wrapped around images of accelerators, experiments and the Fermilab site. The images are often bizarre and fantastical, nearly always impressive. In one drawing, Fermilab’s bison dine at an elegant table; in another, winged creatures stare into a bubbling cauldron that contains the Fermilab accelerator complex and main building, Wilson Hall.

    Gonzales typically worked in pen, sketching intricate details across paper, but she also branched out into different media, crafting jewelry, flags, vases, tables and even the elevator ceiling tiles. Her reach extended to typography, designs around doorways and drawings of things you might not expect: mundane things like emergency preparedness kits and literal nuts and bolts.

    Her word on artistic choices was final. Employees were known to get a talking to if they painted something without consulting Angela. Some colors became tied to the science at hand. One time, an accelerator magnet was painted the wrong shade of blue and thus installed incorrectly, causing some confusion in the control room.

    “Gonzales was at the lab from 1967 to 1998, and in that time she was incredibly influential on the style of the lab,” says Valerie Higgins, Fermilab’s archivist. “But you can see how these tendrils of art spiral out to influence the science and the shape of the lab as well.”

    More than 100 pieces by Gonzales were featured in a Fermilab art gallery exhibit earlier this year, as the lab celebrated its 50th anniversary. “A Lasting Mark” ran from June to September before briefly traveling and then being retired. An online catalog of the exhibit is available on the Fermilab site.

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    Angela Gonzales incorporated many Fermilab elements into the unofficial Fermilab seal, including Wilson Hall, the logo, particle symbols, and buildings and sculptures from around the site. Fermilab.

    4

    Wilson Hall sits among other famous buildings (such as the Leaning Tower of Pisa and the Great Pyramid of Giza) on the cover of the Fermilab Annual Report (1990). Fermilab.

    5
    Gonzales’s artwork also touched the physical spaces at the lab. This image shows her design for the elevator ceiling tiles.
    Fermilab.

    7

    The Fermilab logo was created in a collaboration between Wilson and Gonzales; the final version has rigorous specifications.
    Fermilab.

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 1:15 pm on November 7, 2017 Permalink | Reply
    Tags: a 200-billion-electronvolt proton synchrotron the world’s largest particle accelerator, , Bob Wilson, FNAL, , , , The Main Ring story   

    From FNAL: “Main Ring period: The darkest-turned-happiest days at Fermilab” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    November 6, 2017
    Ryuji Yamada

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    This aerial view shows the Main Ring in 1970. Photo: Fermilab

    It was the spring of 1967. The scene was a vast stretch of cornfields that were at one time the Illinois prairie, where many bison roamed. There stood the newly elected director of National Accelerator Laboratory, Bob Wilson. Born in Frontier, Wyoming, Wilson was filled with a pioneering spirit, both in science and humanity. He stood there with a vision of a 200-billion-electronvolt proton synchrotron, the world’s largest particle accelerator, up and running there in less than five years, a task that he was going to accomplish with a budget of $250 million.

    FNAL Tevatron

    FNAL/Tevatron map


    FNAL/Tevatron DZero detector


    FNAL/Tevatron CDF detector

    Bob Wilson himself drew up the basic design of the magnets of the Main Ring — the 4-mile, circular accelerator that would ramp up particles to the desired energy. For the sake of economy, he would settle on an unconventional and extremely compact, but still functional, mechanical and magnetic structure. The insulation of the conductor was Epoxy-impregnated glass fiber, only approximately 2 millimeters thick. I worked on the detailed design of the dipole magnet, not just for operation at energies of 200 to 400 billion electronvolts, or BeV, but also to be operable up to 500 BeV. For these calculations I used the Argonne National Laboratory’s largest IBM machine to its full capacity of 2 to 4 megabytes over many weekends. I also designed and constructed the correction dipoles and the Main Ring beam detection system. John Schivel worked on the quadrupole magnet design.

    The construction of the Main Ring magnets then proceeded at breakneck speed. We produced 774 dipole magnets — which steer the particle beam — and 240 quadrupole magnets — which focus the beam — as well as some extra spares in time for installation. We began installing the magnets into the Main Ring tunnel during the severe, cold of the winter of 1970 and through the following spring, when the air inside the tunnel was quite humid. It was the worst condition for magnet installation. The last magnet was installed in the tunnel on April 16, 1971.

    The revolutionary and digital solid-state power supply, using thyristors and the power grid line, was designed by Dick Cassel and was implemented by his group, including Howard Pfeffer.

    An unexpected crisis

    On Feb. 26, 1971, we enthusiastically began the beam injection study into the Main Ring, as soon as the sector A, one-sixth of the whole ring, was available; we did not want to wait for all magnets to be installed. We could lead the injected beam through the whole of Sector A with one day’s operation. This was a rather easy job.

    While we were continuing the injection study, on April 22, six days after the installation of the final magnet, we found that two magnets were shorted to ground. The ground insulation of the coil was broken, and we could not continue the operation.

    Even though we had discussed the remote possibility of shorting of a magnet due to radiation damage, which might cause the eventual degradation of the thin Epoxy-impregnated glass fiber insulation layer, this came as a great shock for the Main Ring Magnet group.

    “Now what can we do?” We decided that the physicists would continue testing the Main Ring with the injection beam during the night, while the engineers and technicians replaced the shorted Main Ring magnets during the day.

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    Wilson Hall is named for founding director Robert Wilson. The title of the obelisk, “Acqua Alle Funi,” means “water to the ropes” and was Wilson’s courageous advice to those building the Main Ring. Photo: Reidar Hahn

    The physicists usually worked two shifts: the night and the midnight shifts. Sometimes they took three shifts. I usually took the night shifts. We ran the Main Ring continually, even over the weekends. For this reason, we brought in two beds into the basement room, under the Main Control Room. At some point, I started having pain in my neck and could not turn my head. For a while, there was a nurse standing in the back of the control room during the night shift.

    The atmosphere in the control room changed from very strong optimism to ordinary optimism. The primary questions were: Why were the magnets shorting? How we could fix the damaged magnets quickly enough? Underlying it all was the concern: How soon could we achieve a circulating beam and eventually attain 200 BeV?

    During a six-month period, from the start of the Main Ring beam injection in February to July, approximately 350 Main Ring magnets out of a total of 1,014 were replaced. That came to an average rate two magnets per day. The shorting and replacing of magnets continued afterward, and roughly half of them were replaced over two years.

    Bob Wilson often visited us in the control room late at night. On one occasion, he wanted to try to tune the Main Ring beam himself. On another occasion, he brought in a book and started reading loudly from it in the control room. To me it was all Greek, but it turned out to be Italian. After reading it, he explained it to me that it was “Acqua alle funi.” It was what we needed at that time — intelligent and courageous advice: “Water to the ropes!”

    A few days later, he visited me again in the control room and told me, “Ryuji, we may have to close the lab. Although I asked you to come and work with me on this project, I’m sorry, I may have to close the lab and ask you to go back to Japan.”

    In reality, this was a common opinion outside of Fermilab during this crisis period. Many West Coast physicists were very tough on Bob, and many East Coast physicists had similar opinions. Before Bob Wilson was elected as the director of the National Accelerator Laboratory, there had been a solid 200-BeV proposal published by the Berkeley group. But Bob Wilson was nominated as the director on the strength of his drastically simplified, economical and superior plan.

    Even inside Fermilab there were some pessimistic staff who had little hopes for the success of the Main Ring.

    First one turn, then another: observing the emergence of life in the Main Ring magnets

    For 10 days starting June 24, we were lucky enough to have 180 hours to concentrate on the Main Ring injection study. Although I had installed the position-sensitive electrical pickups around the ring, they were not yet connected to the control room.

    But all correction dipole magnets were controllable from the control room. So one shift person had to stay in the control room, and the other shift person had to go around the ring on a truck, carrying an oscilloscope, and had to communicate with the operator in the control room by a telephone.

    Therefore this was a cumulative effort from shift to shift and day to day. Many physicists were involved for this operation, including Helen and Don Edwards, Ernie Malumud, Ryuji Yamada, David Sutter, Chuck Schmidt, Sigeki Mori, Frank Cole and Al Maschke.

    On June 29, 1971, Chuck Schmidt was in the control room. Al Maschke was going around the service buildings, while Dick Cassel was on shift for power supply. With the instruction from Al, Chuck was adjusting the correction magnets, steering the beam for the next service building. They worked for a long run. At midnight of June 30, we started our shift, continuing the same procedure. Around 7 a.m., we succeeded in getting the first turn of beam around the Main Ring, achieving the first goal. Soon the next shift, by Shigeki More, started. Together with the people who had congregated in the control room — including Bob Wilson, Deputy Director Ned Goldwasser and Ernie Malumud — we celebrated without any drink.

    It was a first excitement for the people at that place at that time. Now we could see a faint second light spot on the meshed fluorescent target at the injection point. It was really dancing on the screen due to the fluctuation of magnet current. And on the special intensity beam monitor of my own design, we could see a clear second pulse 21 microseconds later, although much attenuated.

    On the night of July 2, 1971, I was on shift, and we achieved up to eight turns around the ring of the injected beam. Again this helped us to gain back more confidence. In order to see the multiturn circulation beam as well as the injected beam, we had to remove all meshed targets. Now we could see the clear, sequenced but decaying signal pulses 21 microseconds apart on my detector.

    “Sure enough, the Main Ring is working. It is not dead. It shows sign of life!!”

    After the Fourth of July holiday came days of replacement and improvements of a series of magnets. On Aug. 2, 1971, Shigeki Mori took the shift for injection study, and we attained a coasting beam that went over 10,000 turns.

    We then thought we could start accelerating the beam. But when we accelerated the beam up by 0.5 BeV above the injection energy of 7 BeV, we hit a brick wall. All the physicists desperately started going around the tunnel trying to solve the problem.

    Another obstacle

    A group of physicists, headed by Drasko Jovanovic, started installing simple radiation monitor cans around the ring to find the problematic location. But they could not find any localized trouble spots. Rather, they found that the trouble spots were all around the ring.

    Then I thought of the damaging possibility of stainless steel slivers. These slivers were made when we changed the shorted magnet by cutting open the round welded vacuum pipe at the end of a magnet. When a new magnet was installed, some of the slivers were left inside unintentionally. So when the magnets were excited to a higher field, they were pulled inside the magnet gap, stood up and stopped the beam, because they were slightly magnetic material. (The detailed story is described in the Oct. 10, 2016, news story Japanese influence a steady source of innovation at Fermilab.

    The next big question became, How we could clean these slivers, scattered throughout the Main Ring, after having replaced over 300 magnets already? I proposed pulling a permanent magnet through the vacuum pipes. The following question was, “How?”

    Then an English engineer, Bob Sheldon, said, “In England, we use a ferret to hunt rabbits in small but long underground holes.” We thus obtained a ferret named Felicia. Unfortunately, she refused to go inside the small, dark metallic hole. (Later on, however, she helped us with a larger beam pipe.)

    Hans Kautzky then had a brilliant idea. He suggested using the principle of a blow gun. He made a dozen Mylar disks, shaped to different shapes of the vacuum pipes. He then attached them in sequence on a stainless rod and added a very flexible stainless cable. Then he inserted the assembly into a vacuum pipe in a sector of the Main Ring and pushed it with compressed air from one end. It flew through the vacuum pipe easily. We were thus able to put a 700-meter-long cable through the vacuum pipe. Using this cable, we pulled a harness with a permanent magnet. With 12 operations, we could make it around the entire ring. This way we could clean the whole vacuum pipe, though not perfectly. This operation took about a whole month.

    (There were many reasons for a magnet shorting. The main reason was poor quality control in making joints for the water-cooled copper conductors. The mating surfaces of a butt weld joint were sometimes not completely parallel, and the resulting joint might have a small, wedge-shaped gap. Later, improved welding with an inserted pipe was used.)

    Acceleration to 100 BeV and 200 BeV

    After cleaning the Main Ring vacuum tubes, we could accelerate the Main Ring beam steadily up to 20 BeV. On Jan. 22, 1972, we had a stable 20-BeV beam from pulse to pulse. Jim Griffin was working on the Main Ring radio-frequency system in the F Service Building.

    We did not have any serious problem going over the transition energy of 17.4 BeV. On Feb. 4, 1972, we achieved 53-BeV beam. And on Feb. 11, 1972, we got 100-BeV beam, surpassing the Russian’s world record of 76 BeV.

    During this period, Don and Helen Edwards fixed the tracking problem between the dipole and quadruple magnet power supply.

    On March 1, 1972, Frank Cole was the captain of operations, and I was the co-captain. On these days, we were testing the Main Ring magnets without cooling water to avoid possible shorting of the magnets. We were running the magnet in the “two-mode operation:” 25 short pulses of up to 30 BeV for beam tuning, followed by a 200-BeV pulse, as suggested by Ernie Malamud.

    When the beam trace on the scope crossed 100-BeV line, I called into the control room Director Bob Wilson and others were waiting in the next room.

    Soon the beam trace hit the 200-BeV line — at 1 p.m. on March 1, 1972.

    A wellspring of emotion erupted in the room. Congratulations were exchanged among all present. Bob Wilson and his gathered crew had been waiting for this moment.

    Then all of sudden, boxes of champagne showed up, and Bob started pouring champagne for everybody present.

    On March 3, 1994, we had an 80-year birthday celebration for Bob Wilson in the Fermilab Village. At the end of this party, Bob and I sat in a quiet corner to talk. He told me, “Ryuji, you really saved the lab. You were a hero. Thank you.” I believe that he really intended his thanks for the entire Main Ring group, as well as for all of Fermilab.

    Bob Wilson’s ashes are buried in the old Pioneer Cemetery on the Fermilab site. When Mrs. Jane Wilson died later, her relics were buried next to his.

    See the full article here .

    Please help promote STEM in your local schools.

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 10:50 am on November 1, 2017 Permalink | Reply
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    From FNAL: “Scientists spot explosive counterpart of LIGO/Virgo’s latest gravitational waves” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    October 16, 2017

    Science contact

    Josh Frieman, Director, Dark Energy Survey
    Fermilab
    frieman@fnal.gov
    847-274-0429

    Marcelle Soares-Santos, Assistant Professor
    Brandeis University
    marcelle@brandeis.edu
    773-757-8495

    Daniel Holz, Professor
    University of Chicago
    holz@uchicago.edu
    505-920-5751

    Edo Berger, Professor
    Harvard-Smithsonian Center for Astrophysics
    eberger@cfa.harvard.edu
    617-495-7914

    Media contact

    Andre Salles,
    Fermilab Office of Communication
    asalles@fnal.gov
    630-840-6733

    1
    Artist’s rendition of colliding neutron stars creating gravitational waves and a kilonova. Image: Fermilab

    Scientists using the Dark Energy Camera have captured images of the aftermath of a neutron star collision, the source of LIGO/Virgo’s most recent gravitational wave detection.

    Dark Energy Survey


    Dark Energy Camera [DECam], built at FNAL


    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    A team of scientists using the Dark Energy Camera (DECam), the primary observing tool of the Dark Energy Survey, was among the first to observe the fiery aftermath of a recently detected burst of gravitational waves, recording images of the first confirmed explosion from two colliding neutron stars ever seen by astronomers.

    Scientists on the Dark Energy Survey joined forces with a team of astronomers based at the Harvard-Smithsonian Center for Astrophysics (CfA) for this effort, working with observatories around the world to bolster the original data from DECam. Images taken with DECam captured the flaring-up and fading over time of a kilonova — an explosion similar to a supernova, but on a smaller scale — that occurs when collapsed stars (called neutron stars) crash into each other, creating heavy radioactive elements.

    This particular violent merger, which occurred 130 million years ago in a galaxy near our own (NGC 4993), is the source of the gravitational waves detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo collaborations on Aug. 17.


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    1
    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    This is the fifth source of gravitational waves to be detected — the first one was discovered in September 2015, for which three founding members of the LIGO collaboration were awarded the Nobel Prize in physics two weeks ago.

    This latest event is the first detection of gravitational waves caused by two neutron stars colliding and thus the first one to have a visible source. The previous gravitational wave detections were traced to binary black holes, which cannot be seen through telescopes. This neutron star collision occurred relatively close to home, so within a few hours of receiving the notice from LIGO/Virgo, scientists were able to point telescopes in the direction of the event and get a clear picture of the light.

    2
    The image on the left shows the kilonova (just above and to the left of the brightest galaxy) recorded by the Dark Energy Camera. The image on the right was taken several days later and shows that the kilonova has faded. Image: Dark Energy Survey

    “This is beyond my wildest dreams,” said Marcelle Soares-Santos, formerly of the U.S. Department of Energy’s Fermi National Accelerator Laboratory and currently of Brandeis University, who led the effort from the Dark Energy Survey side. “With DECam we get a good signal, and we can show how it is evolving over time. The team following these signals is a well-oiled machine, and though we did not expect this to happen so soon, we were ready for it.”

    The Dark Energy Camera is one of the most powerful digital imaging devices in existence. It was built and tested at Fermilab, the lead laboratory on the Dark Energy Survey, and is mounted on the National Science Foundation’s 4-meter Blanco telescope, part of the Cerro Tololo Inter-American Observatory in Chile, a division of the National Optical Astronomy Observatory. The DES images are processed at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign.

    Texas A&M University astronomer Jennifer Marshall was observing for DES at the Blanco telescope during the event, while Fermilab astronomers Douglas Tucker and Sahar Allam were coordinating the observations from Fermilab’s Remote Operations Center. “It was truly amazing,” Marshall said. “I felt so fortunate to be in the right place at the right time to help make perhaps one of the most significant observations of my career.”

    The kilonova was first identified in DECam images by Ohio University astronomer Ryan Chornock, who instantly alerted his colleagues by email. “I was flipping through the raw data, and I came across this bright galaxy and saw a new source that was not in the reference image [taken previously],” he said. “It was very exciting.”

    Once the crystal clear images from DECam were taken, a team led by Professor Edo Berger, from CfA, went to work analyzing the phenomenon using several different resources. Within hours of receiving the location information, the team had booked time with several observatories, including NASA’s Hubble Space Telescope and Chandra X-ray Observatory.

    NASA/ESA Hubble Telescope

    NASA/Chandra Telescope

    3
    Composite picture of stars over the Cerro Tololo Inter-American Observatory in Chile. Photo: Reidar Hahn/Fermilab

    LIGO/Virgo works with dozens of astronomy collaborations around the world, providing sky maps of the area where any detected gravitational waves originated. The team from DES and CfA had been preparing for an event like this for more than two years, forging connections with other astronomy collaborations and putting procedures in place to mobilize as soon as word came down that a new source had been detected. The result is a rich data set that covers “radio waves to X-rays to everything in between,” Berger said.

    “This is the first event, the one everyone will remember,” Berger said. “I’m extremely proud of our entire group, who responded in an amazing way. I kept telling them to savor the moment. How many people can say they were there at the birth of a whole new field of astronomy?”

    Adding to the excitement of this observation, this latest gravitational wave detection correlates to a burst of gamma rays spotted by NASA’s Fermi Gamma-ray Space Telescope.

    NASA/Fermi Telescope


    NASA/Fermi LAT

    Combining these detections is like hearing thunder and seeing lightning for the very first time, and it opens up a world of new scientific discovery.

    “Each of these — the gravitational waves from merging neutron stars, the gamma ray burst and the optical counterpart — could have been separate groundbreaking discoveries, and each could have taken many years,” said Daniel Holz of the University of Chicago, who works on both the DES and LIGO collaborations. “In less than a day, we did it all. This has required many different communities working together to make it all happen. It’s so gratifying to have it be so successful.”

    This event also provides a completely new and unique way to measure the present expansion rate of the universe, the Hubble constant, something theorized by Holz and others. Just as astrophysicists use supernovae as “standard candles” (objects of the same intrinsic brightness) to measure cosmic expansion, kilonovae can be used as “standard sirens” (objects of known gravitational wave strength).

    LIGO/Virgo can use this to tell the distance to these events, while optical follow-up from DES and others determines the red shift or recession speed; their combination enables scientists to determine the present expansion rate. This new kind of measurement will assist the Dark Energy Survey in its mission to uncover more about dark energy, the mysterious force accelerating the expansion of the universe.

    “The Dark Energy Survey team has been working with LIGO for more than two years, refining their process of following up gravitational wave signals,” said Fermilab Director Nigel Lockyer. “It is immensely gratifying to be on the front lines of a discovery this significant, one that required the combined skills of many supremely talented people in many fields.”

    The Dark Energy Survey recently began the fifth and final year of its quest to map an area of the southern sky in unprecedented detail. Scientists on DES will use this data to learn more about the effect of dark energy over eight billion years of the universe’s history, in the process measuring 300 million galaxies, 100,000 galaxy clusters and 3,000 supernovae.

    Six papers relating to the DECam discovery of the optical counterpart are planned for publication in The Astrophysical Journal. Preprints of all papers are available here: https://www.darkenergysurvey.org/des-gravitational-waves-papers.

    “It is tremendously exciting to experience a rare event that transforms our understanding of the workings of the universe,” said France A. Córdova, director of the National Science Foundation (NSF), which funds LIGO and supports the observatory where DECam is housed. “This discovery realizes a long-standing goal many of us have had — that is, to simultaneously observe rare cosmic events using both traditional as well as gravitational-wave observatories. Only through NSF’s four-decade investment in gravitational-wave observatories, coupled with telescopes that observe from radio to gamma-ray wavelengths, are we able to expand our opportunities to detect new cosmic phenomena and piece together a fresh narrative of the physics of stars in their death throes.”

    The Dark Energy Survey is a collaboration of more than 400 scientists from 26 institutions in seven countries. Funding for the DES Projects has been provided by the U.S. Department of Energy Office of Science, U.S. National Science Foundation, Ministry of Science and Education of Spain, Science and Technology Facilities Council of the United Kingdom, Higher Education Funding Council for England, ETH Zurich for Switzerland, National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, Kavli Institute of Cosmological Physics at the University of Chicago, Center for Cosmology and AstroParticle Physics at Ohio State University, Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico and Ministério da Ciência e Tecnologia, Deutsche Forschungsgemeinschaft, and the collaborating institutions in the Dark Energy Survey, the list of which can be found at http://www.darkenergysurvey.org/collaboration.

    Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation.

    Fermilab is America’s premier national laboratory for particle physics and accelerator research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC, a joint partnership between the University of Chicago and the Universities Research Association, Inc. Visit Fermilab’s website at http://www.fnal.gov and follow us on Twitter at @Fermilab.

    The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    See the full article here .

    See also:
    https://sciencesprings.wordpress.com/2017/10/20/from-ucsc-neutron-stars-gravitational-waves-and-all-the-gold-in-the-universe/

    From UCSC: “Neutron stars, gravitational waves, and all the gold in the universe”

    5
    6

    Tim Stephens

    Astronomer Ryan Foley says “observing the explosion of two colliding neutron stars” [see https://sciencesprings.wordpress.com/2017/10/17/from-ucsc-first-observations-of-merging-neutron-stars-mark-a-new-era-in-astronomy ]–the first visible event ever linked to gravitational waves–is probably the biggest discovery he’ll make in his lifetime. That’s saying a lot for a young assistant professor who presumably has a long career still ahead of him.

    7
    The first optical image of a gravitational wave source was taken by a team led by Ryan Foley of UC Santa Cruz using the Swope Telescope at the Carnegie Institution’s Las Campanas Observatory in Chile. This image of Swope Supernova Survey 2017a (SSS17a, indicated by arrow) shows the light emitted from the cataclysmic merger of two neutron stars. (Image credit: 1M2H Team/UC Santa Cruz & Carnegie Observatories/Ryan Foley)

    8
    Carnegie Institution Swope telescope at Las Campanas, Chile, 100 kilometres (62 mi) northeast of the city of La Serena. near the north end of a 7 km (4.3 mi) long mountain ridge. Cerro Las Campanas, near the southern end and over 2,500 m (8,200 ft) high, at Las Campanas, Chile

    A neutron star forms when a massive star runs out of fuel and explodes as a supernova, throwing off its outer layers and leaving behind a collapsed core composed almost entirely of neutrons. Neutrons are the uncharged particles in the nucleus of an atom, where they are bound together with positively charged protons. In a neutron star, they are packed together just as densely as in the nucleus of an atom, resulting in an object with one to three times the mass of our sun but only about 12 miles wide.

    “Basically, a neutron star is a gigantic atom with the mass of the sun and the size of a city like San Francisco or Manhattan,” said Foley, an assistant professor of astronomy and astrophysics at UC Santa Cruz.

    These objects are so dense, a cup of neutron star material would weigh as much as Mount Everest, and a teaspoon would weigh a billion tons. It’s as dense as matter can get without collapsing into a black hole.

    THE MERGER

    Like other stars, neutron stars sometimes occur in pairs, orbiting each other and gradually spiraling inward. Eventually, they come together in a catastrophic merger that distorts space and time (creating gravitational waves) and emits a brilliant flare of electromagnetic radiation, including visible, infrared, and ultraviolet light, x-rays, gamma rays, and radio waves. Merging black holes also create gravitational waves, but there’s nothing to be seen because no light can escape from a black hole.

    Foley’s team was the first to observe the light from a neutron star merger that took place on August 17, 2017, and was detected by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO).

    Now, for the first time, scientists can study both the gravitational waves (ripples in the fabric of space-time), and the radiation emitted from the violent merger of the densest objects in the universe.

    9
    The UC Santa Cruz team found SSS17a by comparing a new image of the galaxy N4993 (right) with images taken four months earlier by the Hubble Space Telescope (left). The arrows indicate where SSS17a was absent from the Hubble image and visible in the new image from the Swope Telescope. (Image credits: Left, Hubble/STScI; Right, 1M2H Team/UC Santa Cruz & Carnegie Observatories/Ryan Foley)

    It’s that combination of data, and all that can be learned from it, that has astronomers and physicists so excited. The observations of this one event are keeping hundreds of scientists busy exploring its implications for everything from fundamental physics and cosmology to the origins of gold and other heavy elements.

    A small team of UC Santa Cruz astronomers were the first team to observe light from two neutron stars merging in August. The implications are huge.

    ALL THE GOLD IN THE UNIVERSE

    It turns out that the origins of the heaviest elements, such as gold, platinum, uranium—pretty much everything heavier than iron—has been an enduring conundrum. All the lighter elements have well-explained origins in the nuclear fusion reactions that make stars shine or in the explosions of stars (supernovae). Initially, astrophysicists thought supernovae could account for the heavy elements, too, but there have always been problems with that theory, says Enrico Ramirez-Ruiz, professor and chair of astronomy and astrophysics at UC Santa Cruz.

    9
    The violent merger of two neutron stars is thought to involve three main energy-transfer processes, shown in this diagram, that give rise to the different types of radiation seen by astronomers, including a gamma-ray burst and a kilonova explosion seen in visible light. (Image credit: Murguia-Berthier et al., Science)

    A theoretical astrophysicist, Ramirez-Ruiz has been a leading proponent of the idea that neutron star mergers are the source of the heavy elements. Building a heavy atomic nucleus means adding a lot of neutrons to it. This process is called rapid neutron capture, or the r-process, and it requires some of the most extreme conditions in the universe: extreme temperatures, extreme densities, and a massive flow of neutrons. A neutron star merger fits the bill.

    Ramirez-Ruiz and other theoretical astrophysicists use supercomputers to simulate the physics of extreme events like supernovae and neutron star mergers. This work always goes hand in hand with observational astronomy. Theoretical predictions tell observers what signatures to look for to identify these events, and observations tell theorists if they got the physics right or if they need to tweak their models. The observations by Foley and others of the neutron star merger now known as SSS17a are giving theorists, for the first time, a full set of observational data to compare with their theoretical models.

    According to Ramirez-Ruiz, the observations support the theory that neutron star mergers can account for all the gold in the universe, as well as about half of all the other elements heavier than iron.

    RIPPLES IN THE FABRIC OF SPACE-TIME

    Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity, but until recently they were impossible to observe. LIGO’s extraordinarily sensitive detectors achieved the first direct detection of gravitational waves, from the collision of two black holes, in 2015. Gravitational waves are created by any massive accelerating object, but the strongest waves (and the only ones we have any chance of detecting) are produced by the most extreme phenomena.

    Two massive compact objects—such as black holes, neutron stars, or white dwarfs—orbiting around each other faster and faster as they draw closer together are just the kind of system that should radiate strong gravitational waves. Like ripples spreading in a pond, the waves get smaller as they spread outward from the source. By the time they reached Earth, the ripples detected by LIGO caused distortions of space-time thousands of times smaller than the nucleus of an atom.

    The rarefied signals recorded by LIGO’s detectors not only prove the existence of gravitational waves, they also provide crucial information about the events that produced them. Combined with the telescope observations of the neutron star merger, it’s an incredibly rich set of data.

    LIGO can tell scientists the masses of the merging objects and the mass of the new object created in the merger, which reveals whether the merger produced another neutron star or a more massive object that collapsed into a black hole. To calculate how much mass was ejected in the explosion, and how much mass was converted to energy, scientists also need the optical observations from telescopes. That’s especially important for quantifying the nucleosynthesis of heavy elements during the merger.

    LIGO can also provide a measure of the distance to the merging neutron stars, which can now be compared with the distance measurement based on the light from the merger. That’s important to cosmologists studying the expansion of the universe, because the two measurements are based on different fundamental forces (gravity and electromagnetism), giving completely independent results.

    “This is a huge step forward in astronomy,” Foley said. “Having done it once, we now know we can do it again, and it opens up a whole new world of what we call ‘multi-messenger’ astronomy, viewing the universe through different fundamental forces.”

    IN THIS REPORT

    Neutron stars
    A team from UC Santa Cruz was the first to observe the light from a neutron star merger that took place on August 17, 2017 and was detected by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO)

    10
    Graduate students and post-doctoral scholars at UC Santa Cruz played key roles in the dramatic discovery and analysis of colliding neutron stars.Astronomer Ryan Foley leads a team of young graduate students and postdoctoral scholars who have pulled off an extraordinary coup. Following up on the detection of gravitational waves from the violent merger of two neutron stars, Foley’s team was the first to find the source with a telescope and take images of the light from this cataclysmic event. In so doing, they beat much larger and more senior teams with much more powerful telescopes at their disposal.

    “We’re sort of the scrappy young upstarts who worked hard and got the job done,” said Foley, an untenured assistant professor of astronomy and astrophysics at UC Santa Cruz.

    IN THIS REPORT

    Scientific Papers from the 1M2H Collaboration

    Coulter et al., Science, Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source

    Drout et al., Science, Light Curves of the Neutron Star Merger GW170817/SSS17a: Implications for R-Process Nucleosynthesis

    Shappee et al., Science, Early Spectra of the Gravitational Wave Source GW170817: Evolution of a Neutron Star Merger

    Kilpatrick et al., Science, Electromagnetic Evidence that SSS17a is the Result of a Binary Neutron Star Merger

    Siebert et al., ApJL, The Unprecedented Properties of the First Electromagnetic Counterpart to a Gravitational-wave Source

    Pan et al., ApJL, The Old Host-galaxy Environment of SSS17a, the First Electromagnetic Counterpart to a Gravitational-wave Source

    Murguia-Berthier et al., ApJL, A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a

    Kasen et al., Nature, Origin of the heavy elements in binary neutron star mergers from a gravitational wave event

    Abbott et al., Nature, A gravitational-wave standard siren measurement of the Hubble constant (The LIGO Scientific Collaboration and The Virgo Collaboration, The 1M2H Collaboration, The Dark Energy Camera GW-EM Collaboration and the DES Collaboration, The DLT40 Collaboration, The Las Cumbres Observatory Collaboration, The VINROUGE Collaboration & The MASTER Collaboration)

    Abbott et al., ApJL, Multi-messenger Observations of a Binary Neutron Star Merger

    PRESS RELEASES AND MEDIA COVERAGE


    Watch Ryan Foley tell the story of how his team found the neutron star merger in the video below. 2.5 HOURS.

    Credits

    Writing: Tim Stephens
    Video: Nick Gonzales
    Photos: Carolyn Lagattuta
    Header image: Illustration by Robin Dienel courtesy of the Carnegie Institution for Science
    Design and development: Rob Knight
    Project managers: Sherry Main, Scott Hernandez-Jason, Tim Stephens

    See the full article here .

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

    Please help promote STEM in your local schools.

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 9:22 am on November 1, 2017 Permalink | Reply
    Tags: , FNAL, , Thirty years ago the agreement that established Russian (then USSR) collaboration in the DZero experiment was signed   

    From FNAL: “Three decades of Russian collaboration in DZero” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    November 1, 2017
    Sergei Denisov
    Paul Grannis

    1
    The DZero Muon Group stands in front of one of the six trigger counter planes built by IHEP. Photo: Fred Ullrich

    Thirty years ago, the agreement that established Russian (then USSR) collaboration in the DZero experiment was signed.

    FNAL/Tevatron DZero detector

    The addition of the group from the Institute for High Energy Physics, or IHEP, in Protvino paved the way for a long and fruitful collaboration at the Tevatron that still continues today.

    FNAL Tevatron

    FNAL/Tevatron map


    FNAL/Tevatron DZero detector


    FNAL/Tevatron CDF detector

    The collaborating Russian groups expanded over time and made many crucial contributions to both the detector components and to the physics analyses.

    Although discussions between IHEP and DZero started in 1984, concerns arising from Cold War tensions delayed serious discussions for two years. Once preliminary agreements between Fermilab and IHEP were reached on the framework for collaboration, a visit by DZero leaders to Protvino in spring 1987 was arranged to conduct negotiations on the specific plan. The formal execution of the memorandum of understanding followed in October 1987 with the signing by the directors of Fermilab and Protvino (Leon Lederman and Lev Soloviev), spokespersons of DZero and the IHEP group (Paul Grannis and Sergei Denisov), and the heads of the Fermilab DZero Department and co-spokesman of the IHEP group (Gene Fisk and Alexander Vorobiev). The agreement specified the detector components for which IHEP was responsible, the intended level of manpower commitment to the experiment, and the framework for mutual scientific analyses of the data.

    The IHEP contributions to the Run I detector included the very forward muon toroids and drift tube detectors, as well as the stainless steel absorber plates for the endcap liquid-argon hadron calorimeters. The forward muon detectors were unique at the time in extending the coverage for leptons to within four degrees of the beamlines, thus enabling new physics opportunities. Both contributions were completed on time and shipped to ports in Canada for transfer to Fermilab.

    For Run II, the Russian consortium was expanded to include groups from the Joint Institute for Nuclear Research (JINR) in Dubna, the Institute for Theoretical and Experimental Physics (ITEP) in Moscow, Moscow State University (MSU) and the Petersburg Nuclear Physics Institute (PNPI). The U.S.-Russian Joint Commission on Economic and Technological Cooperation (Gore-Chernomyrdin Commission), established to foster joint U.S.-Russian economic and scientific projects, awarded substantial funds in 1996 for Russian institutes to build major components of the upgraded Run II DZero detector. (As an international organization, JINR was not eligible for Gore-Chernomyrdin funds.) IHEP built the large scintillation counter arrays shown in the photo for triggering on forward muons. JINR constructed the associated mini-drift tube arrays for coordinate measurement, and PNPI built their readout electronics. ITEP provided scintillators for central muon triggering, and Moscow State fabricated large silicon microstrip disks for the forward regions. At the peak of DZero activity during Run II, the IHEP, JINR, ITEP, MSU and PNPI groups had about 20, 20, 5, 10 and 10 people respectively, with typically 10 in residence at Fermilab at a given time.

    The Russian groups have undertaken a variety of high profile physics analyses. These include measurements of small angle b quark and J/psi cross sections; measurements of double parton interactions; the observation of an exotic meson composed of b, c, u and d quarks; and multiple studies of the top quark, including key contributions to the discovery of single-top quark production.

    Despite recurrent problems in securing approvals for visas, the collaboration has been very close and tremendously productive. The long experience of working together on DZero reinforces the oft-mentioned fact that, despite differences between countries at the political level and differing cultural practices, collaboration among scientists working with the shared goal of discovering new physical phenomena is a crucial ingredient for improving understanding and reducing barriers among peoples.

    Sergei Denisov was leader of the IHEP DZero group for the duration of the collaboration. Paul Grannis, current DZero co-spokesperson, also served as spokesperson from 1983-1996.

    See the full article here .

    Please help promote STEM in your local schools.

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 9:03 am on November 1, 2017 Permalink | Reply
    Tags: , FNAL, November at FNAL   

    From FNAL: “This month in Fermilab history: November” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    1
    Neutrinos are the least understood particles in the Standard Model of particle physics.

    November 1971: First neutrinos detected
    In early 1971, NAL Director Robert R. Wilson told the lab’s Users’ Organization that “one of the first aims of experiments on the NAL accelerator system will be the detection of a neutrino. I feel that we then will be in business to do experiments on our accelerator.” Later that year, neutrinos were detected at Fermilab for the first time by E-21, an experiment named “Neutrino Physics at Very High Energies” run by a Caltech group.

    2
    MicroBooNE’s first detection of a neutrino event took place in 2015.

    Nov. 2, 2015: MicroBooNE detects first neutrinos
    On Nov. 2, 2015, MicroBooNE announced that it had detected neutrinos generated by the Fermilab accelerators for the first time. MicroBooNE uses a 170-ton liquid-argon time projection chamber on Fermilab’s Booster neutrino beamline. The detector is part of a phased program moving towards the construction of a much larger time projection chamber detector for DUNE.

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA


    FNAL DUNE Argon tank at SURF


    Surf-Dune/LBNF Caverns at Sanford



    SURF building in Lead SD USA

    3
    The landmark buildings of the early laboratory’s experimental areas are clockwise from left: Proton Pagoda, Meson Lab and Geodesic Dome.

    Nov. 3, 1972: Activation of experimental areas completed
    When it was constructed, the lab had four experimental areas: the Internal Target Area, the Neutrino Area, the Meson Area and the Proton Area. The Internal Target Area was located in the Main Ring. The other three experimental areas each ultimately had a distinctive building: the Geodesic Dome in the Neutrino Area, the Meson Lab (designed by Wilson) in the Meson Area and the Proton Pagoda in the Proton Area. On Nov. 3, 1972, the accelerator sent a beam of protons down the Proton Area experimental line. This marked the complete activation of the experimental areas (the other three were already online).

    4
    The NOvA far detector saw first neutrinos in 2013.

    Nov. 12, 2013: NOvA far detector detects first neutrinos
    The far detector is constructed from PVC and filled with a scintillating liquid that gives off light when a neutrino interacts with it. It detected its first neutrino sent from Fermilab on Nov. 12, 2013.

    FNAL/NOvA experiment map

    5
    President Lyndon B. Johnson signs a bill.

    Nov. 21, 1967: First funds for construction
    On Nov. 21, 1967, at the 89th Congress, President Lyndon B. Johnson signed an appropriations bill authorizing the first funds for the construction of the National Accelerator Laboratory, $7.3 million.

    See the full article here .

    Please help promote STEM in your local schools.

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 3:49 pm on October 26, 2017 Permalink | Reply
    Tags: , , , , , FNAL, ,   

    From The Conversation: “Dark matter: The mystery substance physics still can’t identify that makes up the majority of our universe” 

    FNAL II photo

    Fermilab

    Conversation
    The Conversation

    10.25.17
    Dan Hooper

    1
    Astronomers map dark matter indirectly, via its gravitational pull on other objects. NASA, ESA, and D. Coe (NASA JPL/Caltech and STScI), CC BY

    The past few decades have ushered in an amazing era in the science of cosmology. A diverse array of high-precision measurements has allowed us to reconstruct our universe’s history in remarkable detail.

    And when we compare different measurements – of the expansion rate of the universe, the patterns of light released in the formation of the first atoms, the distributions in space of galaxies and galaxy clusters and the abundances of various chemical species – we find that they all tell the same story, and all support the same series of events.

    This line of research has, frankly, been more successful than I think we had any right to have hoped. We know more about the origin and history of our universe today than almost anyone a few decades ago would have guessed that we would learn in such a short time.

    But despite these very considerable successes, there remains much more to be learned. And in some ways, the discoveries made in recent decades have raised as many new questions as they have answered.

    One of the most vexing gets at the heart of what our universe is actually made of. Cosmological observations have determined the average density of matter in our universe to very high precision. But this density turns out to be much greater than can be accounted for with ordinary atoms.

    After decades of measurements and debate, we are now confident that the overwhelming majority of our universe’s matter – about 84 percent – is not made up of atoms, or of any other known substance. Although we can feel the gravitational pull of this other matter, and clearly tell that it’s there, we simply do not know what it is. This mysterious stuff is invisible, or at least nearly so. For lack of a better name, we call it “dark matter.” But naming something is very different from understanding it.

    For almost as long as we’ve known that dark matter exists, physicists and astronomers have been devising ways to try to learn what it’s made of. They’ve built ultra-sensitive detectors, deployed in deep underground mines, in an effort to measure the gentle impacts of individual dark matter particles colliding with atoms.

    They’ve built exotic telescopes – sensitive not to optical light but to less familiar gamma rays, cosmic rays and neutrinos – to search for the high-energy radiation that is thought to be generated through the interactions of dark matter particles.

    And we have searched for signs of dark matter using incredible machines which accelerate beams of particles – typically protons or electrons – up to the highest speeds possible, and then smash them into one another in an effort to convert their energy into matter. The idea is these collisions could create new and exotic substances, perhaps including the kinds of particles that make up the dark matter of our universe.

    As recently as a decade ago, most cosmologists – including myself – were reasonably confident that we would soon begin to solve the puzzle of dark matter. After all, there was an ambitious experimental program on the horizon, which we anticipated would enable us to identify the nature of this substance and to begin to measure its properties. This program included the world’s most powerful particle accelerator – the Large Hadron Collider – as well as an array of other new experiments and powerful telescopes.

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    2
    Experiments at CERN are trying to zero in on dark matter – but so far no dice. CERN, CC BY-ND

    But things did not play out the way that we expected them to. Although these experiments and observations have been carried out as well as or better than we could have hoped, the discoveries did not come.

    Over the past 15 years, for example, experiments designed to detect individual particles of dark matter have become a million times more sensitive, and yet no signs of these elusive particles have appeared. And although the Large Hadron Collider has by all technical standards performed beautifully, with the exception of the Higgs boson, no new particles or other phenomena have been discovered.

    3
    At Fermilab, the Cryogenic Dark Matter Search uses towers of disks made from silicon and germanium to search for particle interactions from dark matter. Reidar Hahn/Fermilab, CC BY

    The stubborn elusiveness of dark matter has left many scientists both surprised and confused. We had what seemed like very good reasons to expect particles of dark matter to be discovered by now. And yet the hunt continues, and the mystery deepens.

    In many ways, we have only more open questions now than we did a decade or two ago. And at times, it can seem that the more precisely we measure our universe, the less we understand it. Throughout the second half of the 20th century, theoretical particle physicists were often very successful at predicting the kinds of particles that would be discovered as accelerators became increasingly powerful. It was a truly impressive run.

    But our prescience seems to have come to an end – the long-predicted particles associated with our favorite and most well-motivated theories have stubbornly refused to appear. Perhaps the discoveries of such particles are right around the corner, and our confidence will soon be restored. But right now, there seems to be little support for such optimism.

    In response, droves of physicists are going back to their chalkboards, revisiting and revising their assumptions. With bruised egos and a bit more humility, we are desperately attempting to find a new way to make sense of our world.

    See the full article here .

    Please help promote STEM in your local schools.

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    The Conversation US 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.

     
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