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  • richardmitnick 7:29 am on May 23, 2019 Permalink | Reply
    Tags: "Atom smasher could be making new particles that are hiding in plain sight", , , CERN FASER experiment, , Compact Detector for Exotics at LHCb, , Science Magazine   

    From Science Magazine: “Atom smasher could be making new particles that are hiding in plain sight” 

    From Science Magazine

    May. 22, 2019
    Adrian Cho

    In a simulated event, the track of a decay particle called a muon (red), displaced slightly from the center of particle collisions, could be a sign of new physics.

    Are new particles materializing right under physicists’ noses and going unnoticed? The world’s great atom smasher, the Large Hadron Collider (LHC), could be making long-lived particles that slip through its detectors, some researchers say.


    CERN map

    CERN LHC Maximilien Brice and Julien Marius Ordan

    CERN LHC particles

    Next week, they will gather at the LHC’s home, CERN, the European particle physics laboratory near Geneva, Switzerland, to discuss how to capture them.

    They argue the LHC’s next run should emphasize such searches, and some are calling for new detectors that could sniff out the fugitive particles.

    It’s a push born of anxiety. In 2012, experimenters at the $5 billion LHC discovered the Higgs boson, the last particle predicted by the standard model of particles and forces, and the key to explaining how fundamental particles get their masses.

    CERN CMS Higgs Event

    CERN ATLAS Higgs Event

    But the LHC has yet to blast out anything beyond the standard model.

    Standard Model of Particle Physics (LATHAM BOYLE AND MARDUS OF WIKIMEDIA COMMONS)

    “We haven’t found any new physics with the assumptions we started with, so maybe we need to change the assumptions,” says Juliette Alimena, a physicist at Ohio State University (OSU) in Columbus who works with the Compact Muon Solenoid (CMS), one of the two main particle detectors fed by the LHC.

    CERN/CMS Detector

    For decades, physicists have relied on a simple strategy to look for new particles: Smash together protons or electrons at ever-higher energies to produce heavy new particles and watch them decay instantly into lighter, familiar particles within the huge, barrel-shaped detectors. That’s how CMS and its rival detector, A Toroidal LHC Apparatus (ATLAS), spotted the Higgs, which in a trillionth of a nanosecond can decay into, among other things, a pair of photons or two “jets” of lighter particles.


    Long-lived particles, however, would zip through part or all of the detector before decaying. That idea is more than a shot in the dark, says Giovanna Cottin, a theorist at National Taiwan University in Taipei. “Almost all the frameworks for beyond-the-standard-model physics predict the existence of long-lived particles,” she says. For example, a scheme called supersymmetry posits that every standard model particle has a heavier superpartner, some of which could be long-lived. Long-lived particles also emerge in “dark sector” theories that envision undetectable particles that interact with ordinary matter only through “porthole” particles, such as a dark photon that every so often would replace an ordinary photon in a particle interaction.

    CMS and ATLAS, however, were designed to detect particles that decay instantaneously. Like an onion, each detector contains layers of subsystems—trackers that trace charged particles, calorimeters that measure particle energies, and chambers that detect penetrating and particularly handy particles called muons—all arrayed around a central point where the accelerator’s proton beams collide. Particles that fly even a few millimeters before decaying would leave unusual signatures: kinked or offset tracks, or jets that emerge gradually instead of all at once.

    Standard data analysis often assumes such oddities are mistakes and junk, notes Tova Holmes, an ATLAS member from the University of Chicago in Illinois who is searching for the displaced tracks of decays from long-lived supersymmetric particles. “It’s a bit of a challenge because the way we’ve designed things, and the software people have written, basically rejects these things,” she says. So Holmes and colleagues had to rewrite some of that software.

    More important is ensuring that the detectors record the odd events in the first place. The LHC smashes bunches of protons together 400 million times a second. To avoid data overload, trigger systems on CMS and ATLAS sift interesting collisions from dull ones and immediately discard data about 1999 of every 2000 collisions. The culling can inadvertently toss out long-lived particles. Alimena and colleagues wanted to look for particles that live long enough to get stuck in CMS’s calorimeter and decay only later. So they had to put in a special trigger that occasionally reads out the entire detector between the proton collisions.

    Long-lived particle searches had been fringe efforts, says James Beacham, an ATLAS experimenter from OSU. “It’s always been one guy working on this thing,” he says. “Your support group was you in your office.” Now, researchers are joining forces. In March, 182 of them released a 301-page white paper on how to optimize their searches.

    Some want ATLAS and CMS to dedicate more triggers to long-lived particle searches in the next LHC run, from 2021 through 2023. In fact, the next run “is probably our last chance to look for unusual rare events,” says Livia Soffi, a CMS member from the Sapienza University of Rome. Afterward, an upgrade will increase the intensity of the LHC’s beams, requiring tighter triggers.

    Others have proposed a half-dozen new detectors to search for particles so long-lived that they escape the LHC’s existing detectors altogether. Jonathan Feng, a theorist at the University of California, Irvine, and colleagues have won CERN approval for the Forward Search Experiment (FASER), a small tracker to be placed in a service tunnel 480 meters down the beamline from ATLAS.

    CERN FASER experiment schematic

    Supported by $2 million from private foundations and built of borrowed parts, FASER will look for low-mass particles such as dark photons, which could spew from ATLAS, zip through the intervening rock, and decay into electron-positron pairs.

    Another proposal calls for a tracking chamber in an empty hall next to the LHCb, a smaller detector fed by the LHC.

    CERN/LHCb detector

    The Compact Detector for Exotics at LHCb would look for long-lived particles, especially those born in Higgs decays, says Vladimir Gligorov, an LHCb member from the Laboratory for Nuclear Physics and High Energies in Paris.

    The Compact Detector for Exotics at LHCb. https://indico.cern.ch/event/755856/contributions/3263683/attachments/1779990/2897218/PBC2019_CERN_CodexB_report.pdf

    Even more ambitious would be a detector called MATHUSLA, essentially a large, empty building on the surface above the subterranean CMS detector.

    MATHUSLA. http://cds.cern.ch/record/2653848

    Tracking chambers in the ceiling would detect jets spraying up from the decays of long-lived particles created 70 meters below, says David Curtin, a theorist at the University of Toronto in Canada and project co-leader. Curtin is “optimistic” MATHUSLA would cost less than €100 million. “Given that it has sensitivity to this broad range of signatures—and that we haven’t seen anything else—I’d say it’s a no-brainer.”

    Physicists have a duty to look for the odd particles, Beacham says. “The nightmare scenario is that in 20 years, Jill Theorist says, ‘The reason you didn’t see anything is you didn’t keep the right events and do the right search.’”

    See the full article here .


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  • richardmitnick 8:16 am on April 22, 2019 Permalink | Reply
    Tags: , , Hydrophones, MERMAIDs, , Science Magazine   

    From Science Magazine: “These ocean floats can hear earthquakes, revealing mysterious structures deep inside Earth” 

    From Science Magazine

    Apr. 17, 2019
    Erik Stokstad

    A MERMAID undergoes testing off Japan’s coast in 2018. ALEX BURKY/PRINCETON UNIVERSITY

    A versatile, low-cost way to study Earth’s interior from sea has yielded its first images and is scaling up. By deploying hydrophones inside neutrally buoyant floats that drift through the deep ocean, seismologists are detecting earthquakes that occur below the sea floor and using the signals to peer inside Earth in places where data have been lacking.

    In February, researchers reported that nine of these floats near Ecuador’s Galápagos Islands had helped trace a mantle plume—a column of hot rock rising from deep below the islands. Now, 18 floats searching for plumes under Tahiti have also recorded earthquakes, the team reported last week at the European Geosciences Union (EGU) meeting here. “It seems they’ve made a lot of progress,” says Barbara Romanowicz, a geophysicist at the University of California, Berkeley.

    The South Pacific fleet will grow this summer, says Frederik Simons, a seismologist at Princeton University who helped develop the floats, called MERMAIDs (mobile earthquake recorders in marine areas by independent divers). He envisions a global flotilla of thousands of these wandering devices, which could also be used to detect the sound of rain or whales, or outfitted with other environmental or biological sensors. “The goal is to instrument all the oceans.”

    For decades, geologists have placed seismometers on land to study how powerful, faraway earthquakes pass through Earth. Deep structures of different density, such as the cold slabs of ocean crust that sink into the mantle along subduction zones, can speed up or slow down seismic waves. By combining seismic information detected in various locations, researchers can map those structures, much like 3D x-ray scans of the human body. Upwelling plumes and other giant structures under the oceans are more mysterious, however. The reason is simple: There are far fewer seismometers on the ocean floor.

    Such instruments are expensive because they must be deployed and retrieved by research vessels. And sometimes they fail to surface after yearlong campaigns. More recently, scientists have begun to use fiber optic communication cables on the sea floor to detect quakes, but the approach is in its infancy.

    MERMAIDs are a cheap alternative. They drift at a depth of about 1500 meters, which minimizes background noise and lessens the energy needed for periodic ascents to transmit fresh data. Whenever a MERMAID’s hydrophone picks up a strong sound pulse, its computer evaluates whether that pressure wave likely originated from seafloor shaking. If so, the MERMAID surfaces within a few hours and sends the seismogram via satellite.

    The nine floats released near the Galápagos in 2014 gathered 719 seismograms in 2 years before their batteries ran out. Background noise, such as wind and rain at the ocean surface, drowned out some of the seismograms. But 80% were helpful in imaging a mantle plume some 300 kilometers wide and 1900 kilometers deep, the team described in February in Scientific Reports. The widely dispersed MERMAIDs sharpened the picture, compared with studies done with seismometers on the islands and in South America. “The paper demonstrates the potential of the methodology, but I think they need to figure out how to beat down the noise a little more,” Romanowicz says.

    Since that campaign, the MERMAID design was reworked by research engineer Yann Hello of Geoazur, a geoscience lab in Sophia Antipolis, France. He made them spherical and stronger, and tripled battery life. The floats now cost about $40,000, plus about $50 per month to transmit data. “The MERMAIDs are filling a need for a fairly inexpensive, flexible device” to monitor the oceans, says Martin Mai, a geophysicist at King Abdullah University of Science and Technology in Thuwal, Saudi Arabia.

    Between June and September of 2018, 18 of these new MERMAIDs were scattered around Tahiti to explore the Pacific Superswell, an expanse of oddly elevated ocean crust, likely inflated by plumes. The plan is to illuminate this plumbing and find out whether multiple plumes stem from a single deep source. “It’s a pretty natural target,” says Catherine Rychert, a seismologist at the University of Southampton in the United Kingdom. “You’d need a lot of ocean bottom seismometers, a lot of ships, so having floats out there makes sense.”

    So far, the MERMAIDs have identified 258 earthquakes, Joel Simon, a graduate student at Princeton, told the EGU meeting. About 90% of those have also been detected by other seismometers around the world—an indication that the hydrophones are detecting informative earthquakes. Simon has also identified some shear waves, or S-waves, which arrive after the initial pressure waves of a quake and can provide clues to the mantle’s composition and temperature. “We never set out to get S-waves,” he said. “This is incredible.” S-waves can’t travel through water, so they are converted to pressure waves at the sea floor, which saps their energy and makes them hard to identify.

    In August, 28 more MERMAIDS will join the South Pacific fleet, two dozen of them bought by the Southern University of Science and Technology in Shenzhen, China. Heiner Igel, a geophysicist at Ludwig Maximilian University in Munich, Germany, cheers the expansion. “I would say drop them all over the oceans,” he says.

    See the full article here .


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  • richardmitnick 11:10 am on April 3, 2019 Permalink | Reply
    Tags: "Last-minute deal grants European money to U.K.-based fusion reactor", Culham Centre for Fusion Energy (CCFE)-home of JET, , ITER experimental tokamak nuclear fusion reactor, Science Magazine, The Joint European Torus tokamak-JET   

    From Science Magazine: “Last-minute deal grants European money to U.K.-based fusion reactor” 

    From Science Magazine

    Mar. 29, 2019
    Daniel Clery

    The Joint European Torus tokamak generator based at the Culham Center for Fusion Energy located at the Culham Science Centre, near Culham, Oxfordshire, England

    The walls of the Joint European Torus fusion reactor are lined with the same materials as ITER, a much larger fusion reactor under construction.
    ©EUROfusion (CC BY)

    ITER experimental tokamak nuclear fusion reactor that is being built next to the Cadarache facility in Saint Paul les-Durance south of France

    At the eleventh hour, the European Union has agreed to fund Europe’s premier fusion research facility in the United Kingdom—even if the United Kingdom leaves the European Union early next month. The decision to provide €100 million to keep the Joint European Torus (JET) running in 2019 and 2020 will come as a relief both to fusion researchers building the much larger ITER reactor near Cadarache in France and the 500 JET staff working in Culham, near Oxford, U.K.

    “Now we have some certainty over JET,” says Ian Chapman, director of the Culham Centre for Fusion Energy (CCFE), which hosts the JET. But the agreement does not guarantee the JET’s future beyond the end of next year, nor does it ensure that U.K. scientists will be able to participate in European fusion research programs.

    Until the $25 billion ITER is finished in 2025, the JET is the largest fusion reactor in the world. In 2011, the interior surface of its reactor vessel was relined with the same material ITER will use, tungsten and beryllium, making the JET the best simulator for understanding the behavior of its giant cousin.

    The JET was built in the 1970s and ’80s as part of Euratom, a European agreement governing nuclear research. In recent years, CCFE has been managing the JET on behalf of Euratom. But Brexit, the threat of the United Kingdom’s departure from the European Union, has clouded the reactor’s future. The U.K. government has said it also intends to withdraw from Euratom, a separate treaty than the one that governs the European Union. The U.K. government wishes to become an associate member of Euratom, a position that Switzerland holds, so it can continue to participate in research and training. But that agreement cannot be negotiated until after Brexit, which could come as soon as 12 April—or not. With the United Kingdom’s future relationship with Europe still a matter of heated debate, so is its partnership with Euratom.

    CCFE was contracted to manage the JET until the end of 2018. The agreement announced today keeps the JET running until the end of 2020 with €100 million from Euratom. “There is no Brexit clause,” Chapman says, so whatever happens in the coming weeks, the JET is safe for now.

    The JET is essential for ITER preparations, not just because of its inner wall, but because it is the only reactor in the world equipped to run with the same sort of fuel ITER will use, a mixture of deuterium and tritium, both isotopes of hydrogen. In 2020, researchers hope to study how this fuel behaves in the revamped the JET to make it easier to get ITER up to full performance. “It’s a really important experiment,” Chapman says. “We need to demonstrate that we can get a high-performance plasma with a tungsten-beryllium wall. It’s never been done with deuterium-tritium before.”

    Beyond 2020, the JET’s future is uncertain, even aside from Brexit. Euratom and ITER would both like to keep the JET running to carry out more studies up until 2024. Ultimately, that depends on it winning funding in the European Union’s next funding cycle, which begins in 2021. But a question still hangs over what sort of relationship the United Kingdom will have with Euratom by that time. “That uncertainty has not gone away,” Chapman says.

    See the full article here .


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  • richardmitnick 8:57 am on March 31, 2019 Permalink | Reply
    Tags: "Physicists predict a way to squeeze light from the vacuum of empty space", , , , Science Magazine   

    From Science Magazine: “Physicists predict a way to squeeze light from the vacuum of empty space” 

    From Science Magazine

    Mar. 29, 2019
    Adrian Cho

    Charged particles zipping through water in a nuclear reactor produce Cherenkov radiation. Credit: Argonne National Laboratory/Wikimedia commons (CC BY-SA 2.0)

    Cherenkov Radiation. Credit Nuclear-Power.net

    Talk about getting something for nothing. Physicists predict that just by shooting charged particles through an electromagnetic field, it should be possible to generate light from the empty vacuum. In principle, the effect could provide a new way to test the fundamental theory of electricity and magnetism, known as quantum electrodynamics, the most precise theory in all of science. In practice, spotting the effect would require lasers and particle accelerators far more powerful than any that exist now.

    “I’m quite confident about [the prediction] simply because it combines effects that we understand pretty well,” says Ben King, a laser-particle physicist at the University of Plymouth in the United Kingdom, who was not involved in the new analysis. Still, he says, an experimental demonstration “is something for the future.”

    Physicists have long known that energetic charged particles can radiate light when they zip through a transparent medium such as water or a gas. In the medium, light travels slower than it does in empty space, allowing a particle such as an electron or proton to potentially fly faster than light. When that happens, the particle generates an electromagnetic shockwave, just as a supersonic jet creates a shockwave in air. But whereas the jet’s shockwave creates a sonic boom, the electromagnetic shockwave creates light called Cherenkov radiation. That effect causes the water in the cores of nuclear reactors to glow blue, and it’s been used to make particle detectors.

    However, it should be possible to ditch the material and produce Cherenkov light straight from the vacuum, predict Dino Jaroszynski, a physicist at the University of Strathclyde in Glasgow, U.K., and colleagues. The trick is to shoot the particles through an extremely intense electromagnetic field instead.

    According to quantum theory, the vacuum roils with particle-antiparticle pairs flitting in and out of existence too quickly to observe directly. The application of a strong electromagnetic field can polarize those pairs, however, pushing positive and negative particles in opposite directions. Passing photons then interact with the not-quite-there pairs so that the polarized vacuum acts a bit like a transparent medium in which light travels slightly slower than in an ordinary vacuum, Jaroszynski and colleagues calculate.

    Putting two and two together, an energetic charged particle passing through a sufficiently strong electromagnetic field should produce Cherenkov radiation, the team reports in a paper in press at Physical Review Letters. Others had suggested vacuum Cherenkov radiation should exist in certain situations, but the new work takes a more fundamental and all-encompassing approach, says Adam Noble, a physicist at Strathclyde.

    Spotting vacuum Cherenkov radiation would be tough. First, the polarized vacuum slows light by a tiny amount. The electromagnetic fields in the strongest pulses of laser light reduce light’s speed by about a millionth of a percent, Noble estimates. In comparison, water reduces light’s speed by 25%. Second, charged particles in an electromagnetic field spiral and emit another kind of light called synchroton radiation that, in most circumstances, should swamp the Cherenkov radiation.

    Still, in principle, it should be possible to produce vacuum Cherenkov radiation by firing high-energy electrons or protons through overlapping pulses from the world’s highest intensity lasers, which can pack a petawatt, or 1015 watts, of power. However, Jaroszynski and colleagues calculate that in such fields, even particles from the world’s highest energy accelerators would produce much more synchrotron radiation than Cherenkov radiation.

    Space could be another place to look for the effect. Extremely high-energy protons passing through the intense magnetic field of a spinning neutron star—also known as a pulsar—should produce more Cherenkov radiation than synchrotron radiation, the researchers predict. However, pulsars don’t produce many high-energy protons, says Alice Harding, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the particles that do enter a pulsar’s magnetic field should quickly lose energy and spiral instead of zipping across it. “I’m not terribly excited about the prospect for pulsars,” she says.

    Nevertheless, King says, experimenters might see the effect someday. Physicists in Europe are building a trio of 10 petawatt lasers in Romania, Hungary, and the Czech Republic, and their counterparts in China are developing a 100 petawatt laser.

    A laser in Shanghai, China, has set power records yet fits on tabletops. Credit: KAN ZHAN

    Scientists are also trying to create compact laser-driven accelerators that might produce highly energetic particle beams far more cheaply. If those things come together, physicists might be able to spot vacuum Cherenkov radiation, King says.

    Others are devising different ways to use high-power lasers to probe the polarized vacuum. The ultimate aim of such work is to test quantum electrodynamics in new ways, King says. Experimenters have confirmed the theory’s predictions are accurate to within a few parts in a billion. But the theory has never been tested in the realm of extremely strong fields, King says, and such tests are now becoming possible. “The future of this field is quite exciting.”

    See the full article here .


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  • richardmitnick 12:32 pm on March 1, 2019 Permalink | Reply
    Tags: "Department of Energy moves forward with controversial test reactor", a.k.a. the Versatile Fast Neutron Source, “It will give American companies the ability that they currently lack to conduct advanced technology and fuels tests without having to go to our competitors in Russia or China.”, Could also convert nonfissile uranium-238 to plutonium-239 which could be extracted by reprocessing the fuel, Many nuclear engineers envision a future in which the world relies on such fast reactors and reprocessed fuel for its electricity, Science Magazine, The VTR already has friends in both parties in Congress, The VTR would use a fuel richer in uranium-235 that would generate more high-energy neutrons as it “burned.”, VTR-Versatile Test Reactor   

    From Science Magazine: “Department of Energy moves forward with controversial test reactor” 

    From Science Magazine

    Feb. 28, 2019
    Adrian Cho

    A new “fast” nuclear reactor would work a bit like the Experimental Breeder Reactor-II, which ran until 1994 at what is now Idaho National Laboratory.

    The U.S. Department of Energy (DOE) announced today that it will go forward with plans to build a controversial new nuclear reactor that some critics have called a boondoggle. If all goes as planned, the Versatile Test Reactor (VTR) will be built at DOE’s Idaho National Laboratory (INL) near Idaho Falls and will generate copious high-energy neutrons to test new material and technologies for nuclear reactors. That would fill a key gap in the United States’s nuclear capabilities, proponents say. However, some critics have argued that the project is just an excuse to build a reactor of the general type that can generate more fuel than it consumes by “breeding” plutonium.

    “This is a cutting-edge advanced reactor,” said Secretary of Energy Rick Perry at a press conference today at DOE headquarters in Washington, D.C. “It will give American companies the ability that they currently lack to conduct advanced technology and fuels tests without having to go to our competitors in Russia or China.”

    Kemal Pasamehmetoglu, a nuclear engineer at INL who leads the project and was not at the press conference, says, “Obviously, this is very good news. It validates that we need this reactor.”

    The VTR—also known as the Versatile Fast Neutron Source—would be the first reactor DOE has built since the 1970s. It would differ in one key respect from the typical commercial power reactors. Power reactors use a uranium fuel that contains just a few percents of the fissile isotope uranium-235 and are made to be used once and discarded. In contrast, the VTR would use a fuel richer in uranium-235 that would generate more high-energy neutrons as it “burned.” Those neutrons could be used to test how new materials and components age within the core of a conventional nuclear reactor, a key factor in reactor design.

    In principle, such a “fast reactor” could also convert nonfissile uranium-238 to plutonium-239, which could be extracted by reprocessing the fuel. Many nuclear engineers envision a future in which the world relies on such fast reactors and reprocessed fuel for its electricity. Some critics of the nuclear industry claim the VTR is a way to keep that dream alive—although VTR developers do not plan to breed and reprocess fuel.

    The VTR already has friends in both parties in Congress, which in September 2018 gave the project $65 million for this fiscal year—even before DOE had definitely decided it wanted the reactor. However, Pasamehmetoglu urges caution about interpreting the DOE announcement. Strictly speaking, he says, it means the project has passed the first of five milestones—known as “critical decisions”—and that DOE has decided it needs the VTR to fulfill its mission. “It’s just a start,” Pasamehmetoglu says. “It doesn’t mean by any stretch of the imagination that DOE has said that they’re going to go out and build this.”

    Still, Pasamehmetoglu is optimistic. Researchers will now start to work on a conceptual design. They are still a couple of steps away from hammering out a detailed cost estimate and schedule. But Pasamehmetoglu estimates the reactor would cost between $3 billion and $3.5 billion and says the goal is to get it running in 2026. It would be a small 300-megawatt reactor, most likely cooled with liquid sodium, that would not produce electrical power.

    At the press conference, held with Fatih Birol, executive director of the International Energy Agency in Paris, Perry also announced $24 million in new projects on technologies to capture carbon dioxide emissions from industrial plants and sequester the gas underground. “We believe that you can’t have a serious conversation about reducing emissions without including nuclear energy and carbon capture technologies,” Perry said. He noted projections suggest that in 2040 the world will still depend on fossil fuels for 77% of its energy, and in just the next 18 months U.S. exports of liquid natural gas should climb 150%, Perry said.

    See the full article here .


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  • richardmitnick 3:23 pm on February 27, 2019 Permalink | Reply
    Tags: A one-stop link allowing earth scientists to access all the data they need to tackle big questions such as patterns of biodiversity over geologic time and the distribution of metal deposits also the w, , British Geological Survey, , , Science Magazine, This network of earth science databases called Deep-time Digital Earth (DDE)   

    From Science Magazine: “Earth scientists plan to meld massive databases into a ‘geological Google’’ 

    From Science Magazine

    Feb. 26, 2019
    Dennis Normile

    Deep-time Digital Earth aims to liberate data from collections such as the British Geological Survey’s. British Geological Survey.

    The British Geological Survey (BGS) has amassed one of the world’s premier collections of geologic samples. Housed in three enormous warehouses in Nottingham, U.K., it contains about 3 million fossils gathered over more than 150 years at thousands of sites across the country. But this data trove “was not really very useful to anybody,” says Michael Stephenson, a BGS paleontologist. Notes about the samples and their associated rocks “were sitting in boxes on bits of paper.” Now, that could change, thanks to a nascent international effort to meld earth science databases into what Stephenson and other backers are describing as a “geological Google.”

    This network of earth science databases, called Deep-time Digital Earth (DDE), would be a one-stop link allowing earth scientists to access all the data they need to tackle big questions, such as patterns of biodiversity over geologic time, the distribution of metal deposits, and the workings of Africa’s complex groundwater networks. It’s not the first such effort, but it has a key advantage, says Isabel Montañez, a geochemist at University of California, Davis, who is not involved in the project: funding and infrastructure support from the Chinese government. That backing “will be critical to [DDE’s] success given the scope of the proposed work,” she says.

    In December 2018, DDE won the backing of the executive committee of the International Union of Geological Sciences, which said ready access to the collected geodata could offer “insights into the distribution and value of earth’s resources and materials, as well as hazards—while also providing a glimpse of the Earth’s geological future.” At a meeting this week in Beijing, 80 scientists from 40 geoscience organizations including BGS and the Russian Geological Research Institute are discussing how to get DDE up and running by the time of the International Geological Congress in New Delhi in March 2020.

    DDE grew out of a Chinese data digitization scheme called the Geobiodiversity Database (GBDB), initiated in 2006 by Chinese paleontologist Fan Junxuan of Nanjing University. China had long-running efforts in earth sciences, but the data were scattered among numerous collections and institutions. Fan, who was then at the Chinese Academy of Sciences’s Nanjing Institute of Geology and Paleontology, organized GBDB around the stacks of geologic strata called sections and the rocks and fossils in each stratum.

    Norman MacLeod, a paleobiologist at the Natural History Museum in London who is advising DDE, says GBDB has succeeded where similar efforts have stumbled. In the past, he says, volunteer earth scientists tried to do nearly everything themselves, including informatics and data management. GBDB instead pays nonspecialists to input reams of data gleaned from earth science journals covering Chinese findings. Then, paleontologists and stratigraphers review the data for accuracy and consistency, and information technology specialists curate the database and create software to search and analyze the data. Consistent funding also contributed to GBDB’s success, MacLeod says. Although it started small, Fan says GBDB now runs on “several million” yuan per year.

    Earth scientists outside China began to use GBDB, and it became the official database of the International Commission on Stratigraphy in 2012. BGS decided to partner with GBDB to lift its data “from the page and into cyberspace,” as Stephenson puts it. He and other European and Chinese scientists then began to wonder whether the informatics tools developed for GBDB could help create a broader union of databases. “Our idea is to take these big databases and make them use the same standards and references so a researcher could quickly link them to do big science that hasn’t been done before,” he says.

    The Beijing meeting aims to finalize an organizational structure for DDE. Chinese funding agencies are putting up $75 million over 10 years to get the effort off the ground, Fan says. That level of support sets DDE apart from other cyberinfrastructure efforts “that are smaller in scope and less well funded,” Montañez says. Fan hopes DDE will also attract international support. He envisions nationally supported DDE Centers of Excellence that would develop databases and analytical tools for particular interests. Suzhou, China, has already agreed to host the first of them, which will also house the DDE secretariat.

    DDE backers say they want to cooperate with other geodatabase programs, such as BGS’s OneGeology project, which seeks to make geologic maps of the world available online. But Mohan Ramamurthy, project director of the U.S. National Science Foundation–funded EarthCube project, sees little scope for collaboration with his effort, which focuses on current issues such as climate change and biosphere-geosphere interactions. “The two programs have very different objectives with little overlap,” he says.

    Fan also hopes individual institutions will contribute, by sharing data, developing analytical tools, and encouraging their scientists to participate. Once earth scientists are freed of the drudgery of combing scattered collections, he says, they will have time for more important challenges, such as answering “questions about the evolution of life, materials, geography, and climate in deep time.”

    See the full article here .


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  • richardmitnick 12:33 pm on February 23, 2019 Permalink | Reply
    Tags: Astronomers discover solar system’s most distant object [so far] nicknamed ‘FarFarOut’ ", , , , , Science Magazine   

    From Science Magazine: “Astronomers discover solar system’s most distant object [so far] , nicknamed ‘FarFarOut’ “ 

    From Science Magazine

    Feb. 21, 2019
    Paul Voosen

    The solar system’s most distant object is 140 times farther from the sun than Earth. Credit: NASA/JPL-Caltech

    For most people, snow days aren’t very productive. Some people, though, use the time to discover the most distant object in the solar system.

    That’s what Scott Sheppard, an astronomer at the Carnegie Institution for Science in Washington, D.C., did this week when a snow squall shut down the city. A glitzy public talk he was due to deliver was delayed, so he hunkered down and did what he does best: sifted through telescopic views of the solar system’s fringes that his team had taken last month during their search for a hypothesized ninth giant planet.

    That’s when he saw it, a faint object at a distance 140 times farther from the sun than Earth—the farthest solar system object yet known, some 3.5 times more distant than Pluto. The object, if confirmed, would break his team’s own discovery, announced in December 2018, of a dwarf planet 120 times farther out than Earth, which they nicknamed “Farout.” For now, they are jokingly calling the new object “FarFarOut.” “This is hot off the presses,” he said during his rescheduled talk on 21 February.

    For the better part of a decade, Sheppard and his collaborators—Chad Trujillo at Northern Arizona University in Flagstaff and Dave Tholen at the University of Hawaii in Honolulu—have methodically scoured the night sky with some of the world’s most powerful and wide-angled telescopes. Their insistent search has netted four-fifths of the objects known past 9 billion kilometers from the sun.

    This is not stamp collecting. Clustering in the orbits of these objects can serve as indicators of Planet Nine’s influence. Like Farout, FarFarOut’s orbit is not yet known; until it is, it’s uncertain whether it will stay far enough away from the rest of the solar system to be free of the giant planets’ gravitational tug. If it does, the two could join another of Sheppard’s recent distant discoveries, “the Goblin,” which dovetails with projections of the Planet Nine’s possible orbit.

    It will take several years to determine the orbits of Farout and FarFarOut, and whether they will provide more clues. Meanwhile, with nearly every new moon, Sheppard is back out searching on his preferred telescopes, the Blanco 4-meter in Chile and the Subaru 8-meter in Hawaii. He flies to Chile next week, and Hawaii the week after.

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

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level

    See the full article here .


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  • richardmitnick 10:59 am on February 22, 2019 Permalink | Reply
    Tags: , LLC, Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE, NUSCALE POWER, , Science Magazine   

    From Science Magazine: “Smaller, safer, cheaper: One company aims to reinvent the nuclear reactor and save a warming planet” 

    From Science Magazine

    Feb. 21, 2019
    Adrian Cho

    NuScale researchers want to operate 12 small nuclear reactors from a single control room. They built a mock one in Corvallis, Oregon, to show they can do it.

    To a world facing the existential threat of global warming, nuclear power would appear to be a lifeline. Advocates say nuclear reactors, compact and able to deliver steady, carbon-free power, are ideal replacements for fossil fuels and a way to slash greenhouse gas emissions. However, in most of the world, the nuclear industry is in retreat. The public continues to distrust it, especially after three reactors melted down in a 2011 accident at the Fukushima Daiichi Nuclear Power Plant in Japan. Nations also continue to dither over what to do with radioactive reactor waste. Most important, with new reactors costing $7 billion or more, the nuclear industry struggles to compete with cheaper forms of energy, such as natural gas. So even as global temperatures break one record after another, just one nuclear reactor has turned on in the United States in the past 20 years. Globally, nuclear power supplies just 11% of electrical power, down from a high of 17.6% in 1996.

    Jose Reyes, a nuclear engineer and cofounder of NuScale Power, headquartered in Portland, Oregon, says he and his colleagues can revive nuclear by thinking small. Reyes and NuScale’s 350 employees have designed a small modular reactor (SMR) that would take up 1% of the space of a conventional reactor. Whereas a typical commercial reactor cranks out a gigawatt of power, each NuScale SMR would generate just 60 megawatts. For about $3 billion, NuScale would stack up to 12 SMRs side by side, like beer cans in a six-pack, to form a power plant.

    But size alone isn’t a panacea. “If I just scale down a large reactor, I’ll lose, no doubt,” says Reyes, 63, a soft-spoken native of New York City and son of Honduran and Dominican immigrants. To make their reactors safer, NuScale engineers have simplified them, eliminating pumps, valves, and other moving parts while adding safeguards in a design they say would be virtually impervious to meltdown. To make their reactors cheaper, the engineers plan to fabricate them whole in a factory instead of assembling them at a construction site, cutting costs enough to compete with other forms of energy.

    Spun out of nearby Oregon State University (OSU) here in 2007, NuScale has spent more than $800 million on its design—$288 million from the Department of Energy (DOE) and the rest mainly from NuScale’s backer, the global engineering and construction firm Fluor.

    The design is now working its way through licensing with the Nuclear Regulatory Commission (NRC), and the company has lined up a first customer, a utility association that wants to start construction on a plant in Idaho in 2023.

    NuScale is far from alone. With similar projects rising in China and Russia, the company is riding a global wave of interest in SMRs. “SMRs as a class have a potential to change the economics,” says Robert Rosner, a physicist at the University of Chicago in Illinois who co-wrote a 2011 report on them. In the United States, NuScale is the only company seeking to license and build an SMR. Rosner is optimistic about its prospects. “NuScale has really made the case that they’ll be able to pull it off,” Rosner says.

    For now, NuScale’s reactors exist mostly as computer models. But in an industrial area north of town here, the company has built a full-size mock-up of the upper portion of a reactor. Festooned with pipes, the 8-meter-tall gray cylinder isn’t exactly small. It resembles the conning tower of a submarine, one that has somehow surfaced through the dusty ground. NuScale built it to see if workers could squeeze inside for inspections, says Ben Heald, a NuScale reactor designer. “It’s a great marketing tool.”

    Not everyone thinks NuScale will make the transition from mock-up to reality, however. Dozens of advanced reactor designs have come and gone. And even if NuScale and other startups succeed, the nuclear industry won’t build enough plants quickly enough to matter in the fight against climate change, says Allison Macfarlane, a professor of public policy and geologist at George Washington University in Washington, D.C., who chaired NRC from 2012 through 2014. “Nuclear does not do anything quickly,” she says.

    Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE

    A nuclear reactor is a glorified boiler. Within its core hang ranks of fuel rods, usually filled with pellets of uranium oxide. The radioactive uranium atoms spontaneously split, releasing energy and neutrons that go on to split more uranium atoms in a chain reaction called fission. Heat from the chain reaction ultimately boils water to drive steam turbines and generate electricity.

    Designs vary, but 85% of the world’s 452 power reactors circulate water through the core to cool it and ferry heat to a steam generator that drives a turbine.

    The water plays a second safety role. Power reactors typically use a fuel with a small amount of the fissile isotope uranium-235. The dilute fuel sustains a chain reaction only if the neutrons are slowed to increase the probability that they’ll split other atoms. The cooling water itself serves to slow, or moderate, the neutrons. If that water is lost in an accident, fission fizzles, preventing a runaway chain reaction like the one that blew up a graphite-moderated reactor in 1986 at the Chernobyl Nuclear Power Plant in Ukraine.

    Even after the chain reaction dies, however, heat from the radioactive decay of nuclei created by fission can melt the core. That happened at Fukushima when a tsunami swamped the emergency generators needed to pump water through the plant’s reactors.

    NuScale’s design would reduce such risks in multiple ways. First, in an accident the small cores would produce far less decay heat. NuScale engineers have also cut out the pumps that drive the cooling water through the core, relying instead on natural convection. That design eliminates moving parts that could fail and cause an accident in the first place, says Eric Young, a NuScale engineer. “If it’s not there, it can’t break,” he says.

    NuScale’s new reactor housings offer further protection. A conventional reactor sits within a reinforced concrete containment vessel up to 40 meters in diameter. Each 3-meter-wide NuScale reactor nestles into its own 4.6-meter-wide steel containment vessel, which by virtue of its much smaller diameter can withstand pressures 15 times greater. The vessels sit submerged in a vast pool of water: NuScale’s ultimate line of defense.

    For example, in an emergency, operators can cool the core by diverting steam from the turbines to heat exchangers in the pool. During normal operations, the space between the reactor and the containment vessel is kept under vacuum, like a thermos, to insulate the core and allow it to heat up. But if the reactor overheats, relief valves would pop open to release steam and water into the vacuum space, where they would transfer heat to the pool. Such passive features ensure that in just about any conceivable accident, the core would remain intact, Reyes says.

    To prove that the reactor will behave as predicted, NuScale engineers have constructed a one-third scale model. A 7-meter tall tangle of pipes, valves, and wires lurks in the corner of a lab at OSU’s department of nuclear engineering. The model aims not to run exactly like the real reactor, Young says, but rather to validate the computer models that NRC will use to evaluate the design’s safety. The model’s core heats water not with nuclear fuel but with 56 electric heaters like those in curling irons, Young says. “It’s like a big percolator,” he says. “We set up a test and watch coffee being made for 3 days.”

    Making a reactor smaller has a downside, says M. V. Ramana, a physicist at the University of British Columbia in Vancouver, Canada. A smaller reactor will extract less energy from every ton of fuel, he argues, driving up operating costs. “There’s a reason reactors became larger,” Ramana says. “Inherently, NuScale is giving up the advantages of economies of scale.”

    But small size pays off in versatility, Reyes says. One little reactor might power a plant to desalinate seawater or supply heat for an industrial process. A customized NuScale plant might support a developing country’s smaller electrical grid. And in the developed world, where intermittent renewable sources are growing rapidly, a full 12-pack of reactors could provide steady power to make up for the fitful output of windmills and solar panels. By varying the number of reactors producing power, a NuScale plant could “load follow” and fill in the gaps, Reyes says.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 10:34 am on February 22, 2019 Permalink | Reply
    Tags: "Did volcanic eruptions help kill off the dinosaurs?", A large impact crater in the Gulf of Mexico, A massive asteroid strike 66 million years ago that unleashed towering tsunamis and blotted out the sun with ash causing a plunge in global temperatures, Across what is India today countless volcanic seams opened in the ground releasing a flood of lava resembling last year’s eruptions in Hawaii—except across an area the size of Texas, , Over the course of 1 million years the greenhouse gases from these eruptions could have raised global temperatures and poisoned the oceans leaving life in a perilous state before the asteroid impact, Science Magazine, Some 400000 years before the impact the planet gradually warmed by some 5°C only to plunge in temperature right before the mass extinction, The Deccan Traps,   

    From Science Magazine: “Did volcanic eruptions help kill off the dinosaurs?” 

    From Science Magazine

    Feb. 21, 2019
    Paul Voosen

    The hardened lava flows of the Deccan Traps, in western India, may have played a role in the demise of the dinosaurs. Gerta Keller

    What killed off the dinosaurs? The answer has seemed relatively simple since the discovery a few decades ago of a large impact crater in the Gulf of Mexico. It pointed to a massive asteroid strike 66 million years ago that unleashed towering tsunamis and blotted out the sun with ash, causing a plunge in global temperatures.

    But the asteroid wasn’t the only catastrophe to wallop the planet around this time. Across what is India today, countless volcanic seams opened in the ground, releasing a flood of lava resembling last year’s eruptions in Hawaii—except across an area the size of Texas. Over the course of 1 million years, the greenhouse gases from these eruptions could have raised global temperatures and poisoned the oceans, leaving life in a perilous state before the asteroid impact.

    The timing of these eruptions, called the Deccan Traps, has remained uncertain, however. And scientists such as Princeton University’s Gerta Keller have acrimoniously debated [Science] how much of a role they played in wiping out 60% of all the animal and plant species on Earth, including most of the dinosaurs.

    That debate won’t end today. But two studies published in Science have provided the most precise dates for the eruptions so far—and the best evidence yet that the Deccan Traps may have played some role in the dinosaurs’ demise.

    There’s long been evidence that Earth’s climate was changing before the asteroid hit. Some 400,000 years before the impact, the planet gradually warmed by some 5°C, only to plunge in temperature right before the mass extinction. Some thought the Deccan Traps could be responsible for this warming, suggesting 80% of the lava had erupted before the impact.

    But the new studies counter that old view. In one, Courtney Sprain, a geochronologist at the University of Liverpool in the United Kingdom, and colleagues took three trips to India’s Western Ghats, home of some of the thickest lava deposits from the Deccan Traps. They sampled various basaltic rocks formed by the cooled lava. The technique they used, called argon-argon dating, dates the basalt’s formation, giving a direct sense of the eruptions’ timing.

    The researchers’ dates suggest the eruptions began 400,000 years before the impact, and kicked into high gear afterward, releasing 75% of their total volume [Science]in the 600,000 years after the asteroid strike. If the Deccan Traps had kicked off global warming, their carbon dioxide (CO2) emissions had to come before the lava flows really got going—which, Sprain adds, is plausible, given how much CO2 scientists see leaking from modern volcanoes, even when they’re not erupting.

    The dates, and the increase in lava volume after the impact, also line up with a previous suggestion by Sprain’s team, including her former adviser, Paul Renne, a geochronologist at the University of California, Berkeley, that the two events are directly related: The impact might have struck the planet so hard that it sent the Deccan Traps into eruptive high gear [Science].

    The second study used a different method to date the eruptions. A team including Keller and led by Blair Schoene, a geochronologist at Princeton, looked at zircon crystals [Science] trapped between layers of basalt. These zircons can be precisely dated using the decay of uranium to lead, providing time stamps for the layers bracketing the eruptions. The zircons are also rare: It was a full-time job, lasting several years, to sift them out from the rocks at the 140 sites they sampled.

    The dates recovered from the crystals suggest that the Deccan Traps erupted in four intense pulses [Science] rather than continuously, as Sprain suggests. One pulse occurred right before the asteroid strike. That suggests the impact did not trigger the eruptions, he says. Instead, it’s possible this big volcanic pulse before the asteroid impact did play a role in the extinction, Schoene says. “It’s very tempting to say.” But, he adds, there’s never been a clear idea of how exactly these eruptions could directly cause such extinctions.

    Though the two studies differ, they largely agree on the overall timing of the Deccan eruptions, Schoene says. “If you plot the data sets over each other, there’s almost perfect agreement.”

    This match represents a victory, says Noah McLean, a geochemist at the University of Kansas in Lawrence, who was not involved in either study. For decades, dates produced with these geochronological techniques couldn’t line up. But improved techniques and calibration, McLean says, “helped us go from million-year uncertainties to tight chronologies.”

    Solving the mystery of how the dinosaurs died isn’t just an academic problem. Understanding how the eruptions’ injection of CO2 into the atmosphere changed the planet is vital not only for our curiosity about the dinosaurs’ end, but also as an analog for today, Sprain says. “This is the most recent mass extinction we have,” Sprain says. Teasing apart the roles of the impact and the Deccan Traps, she says, can potentially help us understand where we’re heading.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 11:20 am on February 15, 2019 Permalink | Reply
    Tags: "Physicists create a quantum refrigerator that cools with an absence of light", , , , Near-field photonic cooling through control of the chemical potential of photons, , , Science Magazine,   

    From U Michigan via Science Magazine: “Physicists create a quantum refrigerator that cools with an absence of light” 

    U Michigan bloc

    From University of Michigan


    Science Magazine

    Feb. 14, 2019
    Daniel Garisto

    This new device shows that an LED can cool other tiny objects. Joseph Xu/Michigan Engineering, Communications & Marketing

    For decades, atomic physicists have used laser light to slow atoms zinging around in a gas, cooling them to just above absolute zero to study their weird quantum properties. Now, a team of scientists has managed to similarly cool an object—but with the absence of light rather than its presence. The technique, which has never before been experimentally shown, might someday be used to chill the components in microelectronics.

    In an ordinary laser cooling experiment, physicists shine laser light from opposite directions—up, down, left, right, front, back—on a puff of gas such as rubidium. They tune the lasers precisely, so that if an atom moves toward one of them, it absorbs a photon and gets a gentle push back toward the center. Set it up just right and the light saps away the atoms’ kinetic energy, cooling the gas to a very low temperature.

    But Pramod Reddy, an applied physicist at the University of Michigan in Ann Arbor, wanted to try cooling without the special properties of laser light. He and colleagues started with a widget made of semiconducting material commonly found in video screens—a light-emitting diode (LED). An LED exploits a quantum mechanical effect to turn electrical energy into light. Roughly speaking, the LED acts like a little ramp for electrons. Apply a voltage in the right direction and it pushes electrons up and over the ramp, like kids on skateboards. As electrons fall over the ramp to a lower energy state, they emit photons.

    Crucially for the experiment, the LED emits no light when the voltage is reversed, as the electrons cannot go over the ramp in the opposite direction. In fact, reversing the voltage also suppresses the device’s infrared radiation—the broad spectrum of light (including heat) that you see when you look at a hot object through night vision goggles.

    That effectively makes the device colder—and it means the little thing can work like a microscopic refrigerator, Reddy says. All that’s necessary is to put it close enough to another tiny object, he says. “If you take a hot object and a cold object … you can have a radiative exchange of heat,” Reddy says. To prove that they could use an LED to cool, the scientists placed one just tens of nanometers—the width of a couple hundred atoms—away from a heat-measuring device called a calorimeter. That was close enough to increase the transfer of photons between the two objects, due to a process called quantum tunneling. Essentially, the gap was so small that photons could sometimes hop over it.

    The cooler LED absorbed more photons from the calorimeter than it gave back to it, wicking heat away from the calorimeter and lowering its temperature by a ten-thousandth of a degree Celsius, Reddy and colleagues report this week in Nature. That’s a small change, but given the tiny size of the LED, it equals an energy flux of 6 watts per square meter. For comparison, the sun provides about 1000 watts per square meter. Reddy and his colleagues believe they could someday increase the cooling flux up to that strength by reducing the gap size and siphoning away the heat that builds up in the LED.

    The technique probably won’t replace traditional refrigeration techniques or be able to cool materials below temperatures of about 60 K. But it has the potential to someday be used for cooling microelectronics, according to Shanhui Fan, a theoretical physicist at Stanford University in Palo Alto, California, who was not involved with the work. In earlier work, Fan used computer modeling to predict that an LED could have a sizeable cooling effect if placed nanometers from another object. Now, he said, Reddy and his team have realized that idea experimentally.

    See the full article here .


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    U MIchigan Campus

    The University of Michigan (U-M, UM, UMich, or U of M), frequently referred to simply as Michigan, is a public research university located in Ann Arbor, Michigan, United States. Originally, founded in 1817 in Detroit as the Catholepistemiad, or University of Michigania, 20 years before the Michigan Territory officially became a state, the University of Michigan is the state’s oldest university. The university moved to Ann Arbor in 1837 onto 40 acres (16 ha) of what is now known as Central Campus. Since its establishment in Ann Arbor, the university campus has expanded to include more than 584 major buildings with a combined area of more than 34 million gross square feet (781 acres or 3.16 km²), and has two satellite campuses located in Flint and Dearborn. The University was one of the founding members of the Association of American Universities.

    Considered one of the foremost research universities in the United States,[7] the university has very high research activity and its comprehensive graduate program offers doctoral degrees in the humanities, social sciences, and STEM fields (Science, Technology, Engineering and Mathematics) as well as professional degrees in business, medicine, law, pharmacy, nursing, social work and dentistry. Michigan’s body of living alumni (as of 2012) comprises more than 500,000. Besides academic life, Michigan’s athletic teams compete in Division I of the NCAA and are collectively known as the Wolverines. They are members of the Big Ten Conference.

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