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  • richardmitnick 5:40 pm on February 13, 2018 Permalink | Reply
    Tags: , , Neutrinos, , , The case of the disappearing neutrinos,   

    From CERN Courier: “The case of the disappearing neutrinos” 


    CERN Courier

    1
    Neutrino energy

    Neutrinos are popularly thought to penetrate everything owing to their extremely weak interactions with matter. A recent analysis by the IceCube neutrino observatory at the South Pole proves this is not the case, confirming predictions that the neutrino–nucleon interaction cross section rises with energy to the point where even an object as tiny as the Earth can stop high-energy neutrinos in their tracks.


    U Wisconsin ICECUBE neutrino detector at the South Pole

    By studying a sample of 10,784 neutrino events, the IceCube team found that neutrinos with energies between 6.3 and 980 TeV were absorbed in the Earth. From this, they concluded that the neutrino–nucleon cross-section was 1.30+0.21–0.19 (stat) +0.39–0.43 (syst) times the Standard Model (SM) cross-section in that energy range. IceCube did not observe a large increase in the cross-section as is predicted in some models of physics beyond the SM, including those with leptoquarks or extra dimensions.

    The analysis used the 1km 3 volume of IceCube to collect a sample of upward-going muons produced by neutrino interactions in the rock and ice below and around the detector, selecting 10,784 muons with an energy above 1 TeV. Since the zenith angles of these neutrinos are known to about one degree, the absorber thickness can be precisely determined. The data were compared to a simulation containing atmospheric and astrophysical neutrinos, including simulated neutrino interactions in the Earth such as neutral-current interactions. Consequently, IceCube extended previous accelerator measurements upward in energy by several orders of magnitude, with the result in good agreement with the SM prediction (see figure, above).

    Neutrinos are key to probing the deep structure of matter and the high-energy universe, yet until recently their interactions had only been measured at laboratory energies up to about 350 GeV. The high-energy neutrinos detected by IceCube, partially of astrophysical origin, provide an opportunity to measure their interactions at higher energies.

    In an additional analysis of six years of IceCube data, Amy Connolly and Mauricio Bustamante of Ohio State University employ an alternative approach which uses 58 IceCube-contained events (in which the neutrino interaction took place within the detector) to measure the neutrino cross-section. Although these events mostly have well-measured energies, their neutrino zenith angles are less well known and they are also much less numerous, limiting the statistical precision.

    Nevertheless, the team was able to measure the neutrino cross-section in four energy bins from 18 TeV to 2 PeV with factor-of-ten uncertainties, showing for the first time that the energy dependence of the cross section above 18 TeV agrees with the predicted softer-than-linear dependence and reaffirming the absence of new physics at TeV energy scales.

    Future analyses from the IceCube Collaboration will use more data to measure the cross-sections in narrower bins of neutrino energy and to reach higher energies, making the measurements considerably more sensitive to beyond-SM physics. Planned larger detectors such as IceCube-Gen2 and the full KM3NeT can push these measurements further upwards in energy, while even larger detectors would be able to search for the coherent radio Cherenkov pulses produced when neutrinos with energies above 1017 eV interact in ice.

    Proposals for future experiments such as ARA and ARIANNA envision the use of relatively-inexpensive detector arrays to instrument volumes above 100 km3, enough to measure “GZK” neutrinos produced when cosmic-rays interact with the cosmic-microwave background radiation. At these energies, the Earth is almost opaque and detectors should be able to extend cross-section measurements above 1019 eV, thereby probing beyond LHC energies.

    These analyses join previous results on neutrino oscillations and exotic particle searches in showing that IceCube can also contribute to nuclear and particle physics, going beyond its original mission of studying astrophysical neutrinos.

    See the full article here .

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  • richardmitnick 1:58 pm on January 30, 2018 Permalink | Reply
    Tags: Fermilab’s Short-Baseline Neutrino Program, , , , Neutrinos, , , , Short-Baseline Near Detector   

    From Symmetry “Sterile neutrino sleuths” 

    Symmetry Mag

    Symmetry

    01/30/18
    Tom Barratt
    Leah Poffenberger

    FNAL/ICARUS

    FNAL/MicrobooNE

    FNAL Short baseline neutrino detector

    Meet the detectors of Fermilab’s Short-Baseline Neutrino Program, hunting for signs of a possible fourth type of neutrino.

    Neutrinos are not a sociable bunch. Every second, trillions upon trillions of the tiny particles shoot down to Earth from space, but the vast majority don’t stop in to pay a visit—they continue on their journey, almost completely unaffected by any matter they come across.

    Their reluctance to hang around is what makes it such a challenge to study them. But the Short-Baseline Neutrino (SBN) Program at the US Department of Energy’s Fermilab is doing just that: further unraveling the mysteries of neutrinos with three vast detectors filled with ultrapure liquid argon.

    Argon is an inert substance normally found in the air around us—and, once isolated, an excellent medium for studying neutrinos. A neutrino colliding with an argon nucleus leaves behind a signature track and a spray of new particles such as electrons or photons, which can be picked up inside a detector.

    SBN uses three detectors along a straight line in the path of a specially designed neutrino source called the Booster Neutrino Beamline (BNB) at Fermilab. Scientists calculated the exact positions that would yield the most interesting and useful results from the experiment.

    The detectors study a property of neutrinos that scientists have known about for a while but do not have a complete grasp on: oscillations, the innate ability of neutrinos to change their form as they travel. Neutrinos come in three known types, or “flavors”: electron, muon and tau. But oscillations mean each of those types is interchangeable with the others, so a neutrino that begins life as a muon neutrino can naturally transform into an electron neutrino by the end of its journey.

    Some experiments, however, have come up with intriguing results that suggest there could be a fourth type of neutrino that interacts even less than the three types that have already been documented. An experiment at Los Alamos National Laboratory in 1995 showed the first evidence that a fourth neutrino might exist. It was dubbed the “sterile” neutrino because it appears to be unaffected by anything other than gravity. In 2007, MiniBooNE, a previous experiment at Fermilab, showed possible hints of its existence, too, but neither experiment was powerful enough to say if their results definitively demonstrated the existence of a new type of neutrino.

    That’s why it’s crucial to have these three, more powerful detectors. Carefully comparing the findings from all three detectors should allow the best measurement yet of whether a sterile neutrino is lurking out of sight. And finding the sterile neutrino would be evidence of new, intriguing physics—something that doesn’t fit our current picture of the world.

    These three detectors are international endeavors, funded in part by DOE’s Office of Science, the National Science Foundation, the Science and Technology Facilities Council in the UK, CERN, the National Institute for Nuclear Physics (INFN) in Italy, the Swiss National Science Foundation and others. Each helps further develop the technologies, training and expertise needed to design, build and operate another experiment that has been under construction since July: the Deep Underground Neutrino Experiment (DUNE). This international mega-scientific collaboration hosted by Fermilab will send neutrinos 800 miles from Illinois to the massive DUNE detectors, which will be installed a mile underground at the Sanford Underground Research Facility in South Dakota.

    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

    Meet each of the SBN detectors below:

    3
    Artwork by Sandbox Studio, Chicago

    Short-Baseline Near Detector

    Closest to the BNB source at just 110 meters, the Short-Baseline Near Detector (SBND) provides a benchmark for the whole experiment, studying the neutrinos just after they leave the source and before they have a chance to oscillate between flavors. Almost a cube shape, the detecting part of the SBND is four meters tall and wide, five meters long and weighs around 260 tons in total—with a 112-ton active liquid argon volume.

    With a CERN-designed state-of-the-art membrane design for its cooling cryostat—which keeps the argon in a liquid state—SBND is a pioneering detector in the field of neutrino research. It will test new technologies and techniques that will be used in later neutrino projects such as DUNE.

    Due to its proximity to the neutrino source, SBND will collect a colossal amount of interaction data. A secondary, long-term goal of SBND will be to work through this cache to precisely study the physics of these neutrino interactions and even to search for other signs of new physics.

    “After a few years of running, we will have recorded millions of neutrino interactions in SBND, which will be a treasure trove of data that we can use to make many measurements,” says David Schmitz, physicist at the University of Chicago and co-spokesperson for the experiment. “Studying these neutrino interactions in this particular type of detector will have long-term value, especially in the context of DUNE, which will use the same detection principles.”

    The SBND is well on its way to completion; its groundbreaking took place in April 2016 and its components are being built in Switzerland, the UK, Italy and at CERN.

    ___________________________________________
    Stats
    Detector name- SBND (Short-Baseline Near Detector)
    Dimensions- Almost cubic, 4x4x5m (5 meters in beam direction)
    Primary materials- Cryostat and structure made from stainless steel, with polyurethane thermal insulation
    Argon mass- 260 tons in total (112-ton active volume)
    Location- 110 meters from BNB source
    Construction status- Groundbreaking in April 2016, components currently being manufactured in universities and labs around the world
    What makes it unique- Uses membrane cryostat technology, modular TPC construction, and sophisticated electronics operated at cryogenic temperatures, like that which will be used in DUNE; will record millions of neutrino interactions per year
    ___________________________________________

    4
    Artwork by Sandbox Studio, Chicago

    MicroBooNE

    The middle detector, MicroBooNE, was the first of the three detectors to come online. When it did so in 2015, it was the first detector ever to collect data on neutrino interactions in argon at the energies provided by the BNB. The detector sits 360 meters past SBND, nestled as close as possible to its predecessor, MiniBooNE. This proximity is on purpose: MicroBooNE, a more advanced detector, is designed to get a better look at the intriguing results from MiniBooNE.

    In all, MicroBooNE weighs 170 tons (with an active liquid argon volume of 89 tons), making it currently the largest operating neutrino detector in the United States of its kind—a Liquid Argon Time Projection Chamber (LArTPC). That title will transfer to the far detector, ICARUS (see below), upon its installation in 2018.

    While following up on MiniBooNE’s anomaly, MicroBooNE has another important job: providing scientists at Fermilab with useful experience of operating a liquid argon detector, which contributes to the development of new technology for the next generation of experiments.

    “We’ve never in history had more than one liquid argon detector on any beamline, and that’s what makes the SBN Program exciting,” says Fermilab’s Sam Zeller, co-spokesperson for MicroBooNE. “It’s the first time we will have at least two detectors studying neutrino oscillations with liquid argon technology.”

    Techniques used to fill MicroBooNE with argon will pave the way for the gargantuan DUNE far detector in the future, which will hold more than 400 times as much liquid argon as MicroBooNE. Neutrino detectors rely on the liquid inside being extremely pure, and to achieve this goal, all the air normally has to be pumped out before liquid is put in. But MicroBooNE scientists used a different technique: They pumped argon gas into the detector—which pushed all the air out—and then cooled until it condensed into liquid. This new approach will eliminate the need to evacuate the air from DUNE’s six-story-tall detectors.

    Along with contributing to the next generation of detectors, MicroBooNE also contributes to training the next generation of neutrino scientists from around the world. Over half of the collaboration in charge of running MicroBooNE are students and postdocs who bring innovative ideas for analyzing its data.

    ___________________________________________________
    Stats
    Detector name- MicroBooNE (Micro Booster Neutrino Experiment)
    Dimensions- Cylindrical shape (outer), inner TPC: 10.3m long x 2.3m tall x 2.5m wide
    Primary materials- Stainless steel cylinder containing argon vessel and detector elements (stabilized with front and rear supports), polyurethane foam insulation on outer surfaces
    Argon mass- 170 tons in total (89-ton active volume)
    Location- 470 meters from BNB source
    Construction status- Assembled at Fermilab 2012-13, installed in June 2014, has been operating since 2015
    What makes it unique- Used gas-pumped technique to fill with argon; more than half of operators are students or postdocs

    __________________________________________________

    5
    Artwork by Sandbox Studio, Chicago

    ICARUS (Imaging Cosmic And Rare Underground Signals)

    The largest of SBN’s detectors, ICARUS, is also the most distant from the neutrino source—600 meters down the line. Like SBND and MicroBooNE, ICARUS uses liquid argon as a neutrino detection technique, with over 700 tons of the dense liquid split between two symmetrical modules. These colossal tanks of liquid argon, together with excellent imaging capabilities, will allow extremely sensitive detections of neutrino interactions when the detector comes online at Fermilab in 2018.

    The positioning of ICARUS along the neutrino beamline is crucial to its mission. The detector will measure the proportion of both electron and muon neutrinos that collide with argon nuclei as the intense beam of neutrinos passes through it. By comparing this data with that from SBND, scientists will be able to see if the results match with those from previous experiments and explore whether they could be explained by the existence of a sterile neutrino.

    ICARUS, along with MicroBooNE, is also positioned on the Fermilab site close to another neutrino beam, called Neutrinos at the Main Injector (NuMI), which provides neutrinos for the existing experiments at Fermilab and in Minnesota. Unlike the main BNB beam, the NuMI beam will hit ICARUS at an angle through the detector. The goal will be to measure neutrino cross-sections—a measure of their interaction likelihood—rather than their oscillations. The energy of the NuMI beam is similar to that which will be used for DUNE, so ICARUS will provide excellent knowledge and experience to work out the kinks for the huge experiment.

    The detector’s journey has been a long one. From its groundbreaking development, construction and operation in Italy at INFN’s Gran Sasso Laboratory under the leadership of Nobel laureate Carlo Rubbia, ICARUS traveled to CERN in Switzerland in 2014 for some renovation and upgrades. Equipped with new observing capabilities, it was then shipped across the Atlantic to Fermilab in 2017, where it is currently being installed in its future home. Scientists intend to begin taking data with ICARUS in 2018.

    “ICARUS unlocked the potential of liquid argon detectors, and now it’s becoming a crucial part of our research,” says Peter Wilson, head of Fermilab’s SBN program. “We’re excited to see the data coming out of our short-baseline neutrino detectors and apply the lessons we learn to better understand neutrinos with DUNE.”

    _________________________________________
    Stats
    Detector name- ICARUS (Imaging Cosmic And Rare Underground Signals)
    Dimensions- Argon chamber split into two separate argon chambers, each 3.6m long, 3.9m high, 19.6m long
    Primary materials- Detector components held by low-carbon stainless-steel structure, inside cryostat made of aluminum, with thermal shielding layers of boiling nitrogen (to maintain cryostat temperature) and polyurethane thermal insulation
    Argon mass- 760 tons in total (476-ton active volume)
    Location- 600 meters from BNB source
    Construction status- Designed and built in the INFN lab in Pavia, Italy, from the late 1990s, then transferred to the INFN Underground Laboratory at Gran Sasso Laboratory, Italy, where it began operating in 2010. Traveled to CERN for refurbishment in 2014. Arrived at Fermilab in July 2017; currently under installation. Aims to start taking data in 2018.
    What makes it unique- Largest neutrino liquid argon TPC ever built

    _________________________________________

    See the full article here .

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  • richardmitnick 5:11 pm on January 18, 2018 Permalink | Reply
    Tags: , , , Neutrinos, ,   

    From Symmetry: “The biggest little detectors” 

    Symmetry Mag

    Symmetry

    01/18/18
    Leah Hesla

    1
    Photo by Maximilien Brice, CERN

    The ProtoDUNE detectors for the Deep Underground Neutrino Experiment are behemoths in their own right.

    In one sense, the two ProtoDUNE detectors are small. As prototypes of the much larger planned Deep Underground Neutrino Experiment, they are only representative slices, each measuring about 1 percent of the size of the final detector. But in all other ways, the ProtoDUNE detectors are simply massive.

    CERN Proto DUNE Maximillian Brice

    Once they are complete later this year, these two test detectors will be larger than any detector ever built that uses liquid argon, its active material. The international project involves dozens of experimental groups coordinating around the world. And most critically, the ProtoDUNE detectors, which are being installed and tested at the European particle physics laboratory CERN, are the rehearsal spaces in which physicists, engineers and technicians will hammer out nearly every engineering problem confronting DUNE, the biggest international science project ever conducted in the United States.

    Gigantic detector, tiny neutrino

    DUNE’s mission, when it comes online in the mid-2020s, will be to pin down the nature of the neutrino, the most ubiquitous particle of matter in the universe. Despite neutrinos’ omnipresence—they fill the universe, and trillions of them stream through us every second—they are a pain in the neck to capture. Neutrinos are vanishingly small, fleeting particles that, unlike other members of the subatomic realm, are heedless of the matter through which they fly, never stopping to interact.

    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

    Well, almost never.

    Once in a while, scientists can catch one. And when they do, it might tell them a bit about the origins of the universe and why matter predominates over antimatter—and thus how we came to be here at all.

    A global community of more than 1000 scientists from 31 countries are building DUNE, a megascience experiment hosted by the Department of Energy’s Fermi National Accelerator Laboratory. The researchers’ plan is to observe neutrinos using two detectors separated by 1300 kilometers—one at Fermilab outside Chicago and a second one a mile underground in South Dakota at the Sanford Underground Research Facility. Having one at each end enables scientists to see how neutrinos transform as they travel over a long distance.

    The DUNE collaboration is going all-in on the bigger-is-better strategy; after all, the bigger the detector, the more likely scientists are to snag a neutrino. The detector located in South Dakota, called the DUNE far detector, will hold 70,000 metric tons (equivalent to about 525,000 bathtubs) of liquid argon to serve as the neutrino fishing net. It comprises four large modules. Each will stand four stories high and, not including the structures that house the utilities, occupy a footprint roughly equal to a soccer field.

    In short, DUNE is giant.

    Lots of room in ProtoDUNE

    The ProtoDUNE detectors are small only when compared to the giant DUNE detector. If each of the four DUNE modules is a 20-room building, then each ProtoDUNE detector is one room.

    But one room large enough to envelop a small house.

    As one repeatable unit of the ultimate detector, the ProtoDUNE detectors are necessarily big. Each is an enormous cube—about two stories high and about as wide—and contains about 800 metric tons of liquid argon.

    Why two prototypes? Researchers are investigating two ways to use argon and so are constructing two slightly different but equally sized test beds. The single-phase ProtoDUNE uses only liquid argon, while the dual-phase ProtoDUNE uses argon as both a liquid and a gas.

    “They’re the largest liquid-argon particle detectors that have ever been built,” says Ed Blucher, DUNE co-spokesperson and a physicist at the University of Chicago.

    As DUNE’s test bed, the ProtoDUNE detectors also have to offer researchers a realistic picture of how the liquid-argon detection technology will work in DUNE, so the instrumentation inside the detectors is also at full, giant scale.

    “If you’re going to build a huge underground detector and invest all of this time and all of these resources into it, that prototype has to work properly and be well-understood,” says Bob Paulos, director of the University of Wisconsin–Madison Physical Sciences Lab and a DUNE engineer. “You need to understand all the engineering problems before you proceed to build literally hundreds of these components and try to transport them all underground.”

    3
    A crucial step for ProtoDUNE was welding together the cryostat, or cold vessel, that will house the detector components and liquid argon. Photo by CERN.

    Partners in ProtoDUNE

    ProtoDUNE is a rehearsal for DUNE not only in its technical orchestration but also in the coordination of human activity.

    When scientists were planning their next-generation neutrino experiment around 2013, they realized that it could succeed only by bringing the international scientific community together to build the project. They also saw that even the prototyping would require an effort of global proportions—both geographically and professionally. As a result, DUNE and ProtoDUNE actively invite students, early-career scientists and senior researchers from all around the world to contribute.

    “The scale of ProtoDUNE, a global collaboration at CERN for a US-based megaproject, is a paradigm change in the way neutrino science is done,” says Christos Touramanis, a physicist at the University of Liverpool and one of the co-coordinators of the single-phase detector. For both DUNE and ProtoDUNE, funding comes from partners around the world, including the Department of Energy’s Office of Science and CERN.

    The successful execution of ProtoDUNE’s assembly and testing by international groups requires a unity of purpose from parties that could hardly be farther apart, geographically speaking.

    Scientists say the effort is going smoothly.

    “I’ve been doing neutrino physics and detector technology for the last 20 or 25 years. I’ve never seen such an effort go up so nicely and quickly. It’s astonishing,” says Fermilab scientist Flavio Cavanna, who co-coordinates the single-phase ProtoDUNE project. “We have a great collaboration, great atmosphere, great willingness to make it. Everybody is doing his or her best to contribute to the success of this big project. I used to say that ProtoDUNE was mission impossible, because—in the short time we were given to make the two detectors, it looked that way in the beginning. But looking at where we are now, and all the progress made so far, it starts turning out to be mission possible.”

    4
    The anode plane array (APA) [STFC] is prepped for shipment at Daresbury Laboratory in the UK. Christos Touramanis.

    Inside the liquid-argon test bed

    The first signal emerges as a streak of ionization electrons.

    To record the signal, scientists will use something called an anode plane array, or APA. An APA is a screen created using 24 kilometers of precisely tensioned, closely spaced, continuously wound wire. This wire screen is positively charged, so it attracts the negatively charged electrons.

    Much the way a wave front approaches the beach’s shore, the particle track—a string of the ionization electrons—will head toward the positively charged wires inside the ProtoDUNE detectors. The wires will send information about the track to computers, which will record its properties and thus information about the original neutrino interaction.

    A group in the University of Wisconsin–Madison Physical Sciences Lab led by Paulos designed the single-phase ProtoDUNE wire arrays. The Wisconsin group, Daresbury Laboratory in the UK and several UK universities are building APAs for the same detector. The first APA from Wisconsin arrived at CERN last year; the first from Daresbury Lab arrived earlier this week.

    “These are complicated to build,” Paulos says, noting that it currently takes about three months to build just one. “Building these 6-meter-tall anode planes with continuously wound wire—that’s something that hasn’t been done before.”

    The anode planes attract the electrons. Pushing away the electrons will be a complementary set of panels, called the cathode plane. Together, the anode and cathode planes behave like battery terminals, with one repelling electron tracks and the other drawing them in. A group at CERN designed and is building the cathode plane.

    The dual-phase detector will operate on the same principle but with a different configuration of wire arrays. A special layer of electronics near the cathode will allow for the amplification of faint electron tracks in a layer of gaseous argon. Groups at institutions in France, Germany and Switzerland are designing those instruments. Once complete, they will also send their arrays to be tested at CERN.

    Then there’s the business of observing light.

    The flash of light is the result of a release of energy from the electron in the process of getting bumped from an argon atom. The appearance of light is like the signal to start a stopwatch; it marks the moment the neutrino interaction in a detector takes place. This enables scientists to reconstruct in three dimensions the picture of the interaction and resulting particles.

    On the other side of the equator, a group at the University of Campinas in Brazil is coordinating the installation of instruments that will capture the flashes of light resulting from particle interactions in the single-phase ProtoDUNE detector.

    Two of the designs for the single-phase prototype—one by Indiana University, the other by Fermilab and MIT—are of a type called guiding bars. These long, narrow strips work like fiber optic cables: they capture the light, convert it into light in the visible spectrum and finally guide it to an external sensor.

    A third design, called ARAPUCA, was developed by three Brazilian universities and Fermilab and is being partially produced at Colorado State University. Named for the Guaraní word for a bird trap, the efficient ARAPUCA design will be able to “trap” even very low light signals and transmit them to its sensors.

    5
    The ARAPUCA array, designed by three Brazilian universities and Fermilab, was partially produced at Colorado State University. D. Warner, Colorado State University.

    “The ARAPUCA technology is totally new,” says University of Campinas scientist Ettore Segreto, who is co-coordinating the installation of the light detection systems in the single-phase prototype. “We might be able to get more information from the light detection—for example, greater energy resolution.”

    Groups from France, Spain and the Swiss Federal Institute of Technology are developing the light detection system for the dual-phase prototype, which will comprise 36 photomultiplier tubes, or PMTs, situated near the cathode plane. A PMT works by picking up the light from the particle interaction and converting it into electrons, multiplying their number and so amplifying the signal’s strength as the electrons travel down the tube.

    With two tricked-out detectors, the DUNE collaboration can test their picture-taking capabilities and prepare DUNE to capture in exquisite detail the fleeting interactions of neutrinos.

    Bringing instruments into harmony

    But even if they’re instrumented to the nines inside, two isolated prototypes do not a proper test bed make. Both ProtoDUNE detectors must be hooked up to computing systems so particle interaction signals can be converted into data. Each detector must be contained in a cryostat, which functions like a thermos, for the argon to be cold enough to maintain a liquid state. And the detectors must be fed particles in the first place.

    CERN is addressing these key areas by providing particle beam, innovative cryogenics and computing infrastructures, and connecting the prototype detectors with the DUNE experimental environment.

    DUNE’s neutrinos will be provided by the Long-Baseline Neutrino Facility, or LBNF, which held an underground groundbreaking for the start of its construction in July. LBNF, led by Fermilab, will provide the construction, beamline and cryogenics for the mammoth DUNE detector, as well as Fermilab’s chain of particle accelerators, which will provide the world’s most intense neutrino beam to the experiment.

    CERN is helping simulate that environment as closely as possible with the scaled-down ProtoDUNE detectors, furnishing them with particle beams so researchers can characterize how the detectors respond. Under the leadership of scientist Marzio Nessi, last year the CERN group built a new facility for the test beds, where CERN is now constructing two new particle beamlines that extend the lab’s existing network.

    7
    The recently arrived anode plane array (hanging on the left) is moved by a crane to its new home in the ProtoDUNE cryostat. Photo by CERN.

    In addition, CERN built the ProtoDUNE cryostats—the largest ever constructed for a particle physics experiment—which also will serve as prototypes for those used in DUNE. Scientists will be able to gather and interpret the data generated from the detectors with a CERN computing farm and software and hardware from several UK universities.

    “The very process of building these prototype detectors provides a stress test for building them in DUNE,” Blucher says.

    CERN’s beam schedule sets the schedule for testing. In December, the European laboratory will temporarily shut off beam to its experiments for upgrades to the Large Hadron Collider. DUNE scientists aim to position the ProtoDUNE detectors in the CERN beam before then, testing the new technologies pioneered as part of the experiment.

    “ProtoDUNE is a necessary and fundamental step towards LBNF/DUNE,” Nessi says. “Most of the engineering will be defined there and it is the place to learn and solve problems. The success of the LBNF/DUNE project depends on it.”

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 1:53 pm on January 17, 2018 Permalink | Reply
    Tags: , , Neutrinos, , , ,   

    From Physics World: “Neutrino hunter” 

    physicsworld
    physicsworld.com

    Nigel Lockyer

    Nigel Lockyer, director of Fermilab in the US, talks to Michael Banks about the future of particle physics – and why neutrinos hold the key.

    Fermilab is currently building the Deep Underground Neutrino Experiment (DUNE). How are things progressing?

    Construction began last year with a ground-breaking ceremony held in July at the Sanford Underground Research Facility, which is home to 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

    By 2022 the first of four tanks of liquid argon, each 17,000 tonnes, will be in place detecting neutrinos from space. Then in 2026, when all four are installed, Fermilab will begin sending the first beam of neutrinos to DUNE, which is some 1300 km away.

    Why neutrinos?

    Neutrinos have kept throwing up surprises ever since we began studying them and we expect a lot more in the future. In many ways, the best method to study physics beyond the Standard Model is with neutrinos.

    Standard Model of Particle Physics from Symmetry Magazine

    What science do you plan when DUNE comes online?

    One fascinating aspect is detecting neutrinos from supernova explosions. Liquid argon is very good at picking up electron neutrinos and we would expect to see a signal if that occurred in our galaxy. We could then study how the explosion results in a neutron star or black hole. That would really be an amazing discovery.

    And what about when Fermilab begins firing neutrinos towards DUNE?

    One of the main goals is to investigate charge–parity (CP) violation in the lepton sector. We would be looking for the appearance of electron and antielectron neutrinos. If there is a statistical difference then this would be a sign of CP violation and could give us hints as to the reason why there is more matter than antimatter in the universe. Another aspect of the experiment is to search for proton decay.

    How will Fermilab help in the effort?

    To produce neutrinos, the protons smash into a graphite target that is currently the shape of a pencil. We are aiming to quadruple the proton beam power from 700 kW to 2.5 MW. Yet we can’t use graphite after the accelerator has been upgraded due to the high beam power so we need to have a rigorous R&D effort in materials physics.

    What kind of materials are you looking at?

    The issue we face is how to dissipate heat better. We are looking at alloys of beryllium to act as a target and potentially rotating it to cool it down better.

    What are some of the challenges in building the liquid argon detectors?

    So far the largest liquid argon detector is built in the US at Fermilab, which is 170 tonnes. As each full-sized tank at DUNE will be 17,000 tonnes, we face a challenge to scale up the technology. One particular issue is that the electronics are contained within the liquid argon and we need to do some more R&D in this area to make sure they can operate effectively. The other area is with the purity of the liquid argon itself. It is a noble gas and, if pure, an electron can drift forever within it. But if there are any impurities that will limit how well the detector can operate.

    How will you go about developing this technology?

    The amount of data you get out of liquid argon detectors is enormous, so we need to make sure we have all the technology tried and tested. We are in the process of building two 600 tonne prototype detectors, the first of which will be tested at CERN in June 2018.

    CERN Proto DUNE Maximillian Brice

    The UK recently announced it will contribute £65m towards DUNE, how will that be used?

    The UK is helping build components for the detector and contributing with the data-acquisition side. It is also helping to develop the new proton target, and to construct the new linear accelerator that will enable the needed beam power.

    3
    The APA being prepped for shipment at Daresbury Laboratory. (Credit: STFC)

    4
    First APA (Anode Plane Assembly) ready to be installed in the protoDUNE-SP detector Photograph: Ordan, Julien Marius

    Are you worried Brexit might derail such an agreement?

    I don’t think so. The agreement is between the UK and US governments and we expect the UK to maintain its support.

    Japan is planning a successor to its Super Kamiokande neutrino detector – Hyper Kamiokande – that would carry out similar physics. Is it a collaborator or competitor?

    Well, it’s not a collaborator. Like Super Kamiokande, Hyper Kamiokande would be a water-based detector, the technology of which is much more established than liquid argon. However, in the long run liquid argon is a much more powerful detector medium – you can get a lot more information about the neutrino from it. I think we are pursuing the right technology. We also have a longer baseline that would let us look for additional interactions between neutrinos and we will create neutrinos with a range of energies. Additionally, the DUNE detectors will be built a mile underground to shield them from cosmic interference.

    Super-Kamiokande experiment. located under Mount Ikeno near the city of Hida, Gifu Prefecture, Japan

    Hyper-Kamiokande, a neutrino physics laboratory located underground in the Mozumi Mine of the Kamioka Mining and Smelting Co. near the Kamioka section of the city of Hida in Gifu Prefecture, Japan.

    _____________________________________________________
    In the long run liquid argon is a much more powerful detector medium – you can get a lot more information about the neutrino from it.
    _____________________________________________________

    Regarding the future at the high-energy frontier, does the US support the International Linear Collider (ILC)?

    ILC schematic, being planned for the Kitakami highland, in the Iwate prefecture of northern Japan

    The ILC began as an international project and in recent years Japan has come forward with an interest to host it. We think that Japan now needs to take a lead on the project and give it the go-ahead. Then we can all get around the table and begin negotiations.

    And what about plans by China to build its own Higgs factory?

    The Chinese government is looking at the proposal carefully and trying to gauge how important it is for the research community in China. Currently, Chinese accelerator scientists are busy with two upcoming projects in the country: a free-electron laser in Shanghai and a synchrotron in Beijing. That will keep them busy for the next five years, but after that this project could really take off.

    See the full article here .

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    PhysicsWorld is a publication of the Institute of Physics. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application.

    We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.
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  • richardmitnick 2:27 pm on January 16, 2018 Permalink | Reply
    Tags: , , , Neutrinos, , ,   

    From STFC: “UK builds vital component of global neutrino experiment” 


    STFC

    16 January 2018
    Becky Parker-Ellis
    becky.parker-ellis@stfc.ac.uk
    Tel: +44(0)1793 444564
    Mob: +44(0)7808 879294

    1
    The APA being prepped for shipment at Daresbury Laboratory. (Credit: STFC)

    The UK has built an essential piece of the globally-anticipated DUNE experiment, which will study the differences between neutrinos and anti-neutrinos in a bid to understand how the Universe came to be made up of matter.

    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

    Vital components of the DUNE detectors have been constructed in the UK and have now been shipped to CERN for initial testing, marking a significant milestone for the experiment’s progress.

    DUNE (the Deep Underground Neutrino Experiment) is a flagship international experiment run by the United States Department of Energy’s Fermilab [FNAL] that involves over 1,000 scientists from 31 countries. Various elements of the experiment are under construction across the world, with the UK taking a major role in contributing essential expertise and components to the experiment and facility.

    Using a particle accelerator, an intense beam of neutrinos will be fired 800 miles through the earth from Fermilab in Chicago to the DUNE experiment in South Dakota. There the incoming beam will be studied using DUNE’s liquid-argon detector.

    The DUNE project aims to advance our understanding of the origin and structure of the universe. One aspect of study is the behaviour of particles called neutrinos and their antimatter counterparts, antineutrinos. This could provide insight as to why we live in a matter-dominated universe and inform the debate on why the universe survived the Big Bang.

    A UK team has just completed their first prototype Anode Plane Assembly (APA), the largest component of the DUNE detector, to be used in the protoDUNE detector at CERN.

    2
    First APA (Anode Plane Assembly) ready to be installed in the protoDUNE-SP detector Photograph: Ordan, Julien Marius

    CERN Proto DUNE Maximillian Brice

    The APA, which was built at the Science and Technology Facilities Council’s (STFC) Daresbury Laboratory, is the first such anode plane to ever have been built in the UK.

    The APAs are large rectangular steel frames covered with approximately 4000 wires that are used to read the signal from particle tracks generated inside the liquid-argon detector. At 2.3m by 6.3m, the impressive frames are roughly as large as five full-size pool tables led side-by-side.

    Dr Justin Evans of the University of Manchester, who is leading the protoDUNE APA-construction project in the UK, said: “This shipment marks the culmination of a year of very hard work by the team, which has members from STFC Daresbury and the Universities of Manchester, Liverpool, Sheffield and Lancaster. Constructing this anode plane has required relentless attention to detail, and huge dedication to addressing the challenges of building something for the first time. This is a major milestone on our way to doing exciting physics with the protoDUNE and DUNE detectors.”

    These prototype frames were funded through an STFC grant. The 150 APAs that the UK will produce for the large-scale DUNE detector will be paid for as part of the £65million investment by the UK in the UK-US Science and Technology agreement, which was announced in September last year.

    Mechanical engineer Alan Grant has led the organisation of the project on behalf of STFC’s Daresbury Laboratory. He said: “This is an exciting milestone for the UK’s contribution to the DUNE project.

    “The planes are a vital part of the liquid-argon detectors and are one of the biggest component contributions the UK is making to DUNE, so it is thrilling to have the first one ready for shipping and testing.

    “We have a busy few years ahead of us at the Daresbury Laboratory as we are planning to build 150 panels for one of DUNE’s modules, but we are looking forward to meeting the challenge.”

    3
    The ProtoDUNE core installation team members at CERN, in front of the truck from Daresbury. (Credit: University of Liverpool)

    The UK’s first complete APA began the long journey to CERN by road on Friday (January 12), and arrived in Geneva today (January 16). Once successfully tested on the protoDUNE experiment at CERN, a full set of panels will be created and eventually be installed one-mile underground at Fermilab’s Long-Baseline Neutrino Facility (LBNF) in the Sanford Underground Research Facility in South Dakota.

    This is the first such plane to be delivered by the UK to CERN for testing, with the second and third panels set to be shipped in spring. It is expected to take two to three years to produce the full 150 APAs for one module.

    Professor Alfons Weber, of STFC and Oxford University, is the overall Principal Investigator of DUNE UK. He said: “We in the UK are gearing up to deliver several major components for the DUNE experiment and the LBNF facility, which also include the data acquisition system, accelerator components and the neutrino production target. These prototype APAs, which will be installed and tested at CERN, are one of the first major deliveries that will make this exciting experiment a reality.”

    The DUNE APA consortium is led by Professor Stefan Söldner-Rembold of the University of Manchester, with contributions from several other North West universities including Liverpool, Sheffield and Lancaster.

    Professor Söldner-Rembold said: “Each one of the four final DUNE modules will contain 17,000 tons of liquid argon. For a single module, 150 APAs will need to be built which represents a major construction challenge. We are working with UK industry to prepare this large construction project. The wires are kept under tension and we need to ensure that none of the wires will break during several decades of detector operation as the inside of the detector will not be accessible. The planes will now undergo rigorous testing to make sure they are up for the job.

    “Physicists across the world are excited to see what DUNE will be capable of, as unlocking the secrets of the neutrino will help us understand more about the structure of the Universe.

    “Although neutrinos are the second most abundant particle in the Universe, they are enormously difficult to catch as they have very nearly no mass, are not charged and rarely interact with other particles. This is why DUNE is such an exciting experiment and why we are celebrating this milestone in its construction.”

    Christos Touramanis, from the University of Liverpool and co-spokesperson for the protoDUNE project, said: “ProtoDUNE is the first CERN experiment which is a prototype for an experiment at Fermilab, a demonstration of global strategy and coordination in modern particle physics. We in the UK have been instrumental in setting up protoDUNE and in addition to my role we provide leadership in the data acquisition sub-project, and of course anode planes.”

    DUNE will also watch for neutrinos produced when a star explodes, which could reveal the formation of neutron stars and black holes, and will investigate whether protons live forever or eventually decay, bringing us closer to fulfilling Einstein’s dream of a grand unified theory.

    See the full article here .

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    STFC Hartree Centre

    Helping build a globally competitive, knowledge-based UK economy

    We are a world-leading multi-disciplinary science organisation, and our goal is to deliver economic, societal, scientific and international benefits to the UK and its people – and more broadly to the world. Our strength comes from our distinct but interrelated functions:

    Universities: we support university-based research, innovation and skills development in astronomy, particle physics, nuclear physics, and space science
    Scientific Facilities: we provide access to world-leading, large-scale facilities across a range of physical and life sciences, enabling research, innovation and skills training in these areas
    National Campuses: we work with partners to build National Science and Innovation Campuses based around our National Laboratories to promote academic and industrial collaboration and translation of our research to market through direct interaction with industry
    Inspiring and Involving: we help ensure a future pipeline of skilled and enthusiastic young people by using the excitement of our sciences to encourage wider take-up of STEM subjects in school and future life (science, technology, engineering and mathematics)

    We support an academic community of around 1,700 in particle physics, nuclear physics, and astronomy including space science, who work at more than 50 universities and research institutes in the UK, Europe, Japan and the United States, including a rolling cohort of more than 900 PhD students.

    STFC-funded universities produce physics postgraduates with outstanding high-end scientific, analytic and technical skills who on graduation enjoy almost full employment. Roughly half of our PhD students continue in research, sustaining national capability and creating the bedrock of the UK’s scientific excellence. The remainder – much valued for their numerical, problem solving and project management skills – choose equally important industrial, commercial or government careers.

    Our large-scale scientific facilities in the UK and Europe are used by more than 3,500 users each year, carrying out more than 2,000 experiments and generating around 900 publications. The facilities provide a range of research techniques using neutrons, muons, lasers and x-rays, and high performance computing and complex analysis of large data sets.

    They are used by scientists across a huge variety of science disciplines ranging from the physical and heritage sciences to medicine, biosciences, the environment, energy, and more. These facilities provide a massive productivity boost for UK science, as well as unique capabilities for UK industry.

    Our two Campuses are based around our Rutherford Appleton Laboratory at Harwell in Oxfordshire, and our Daresbury Laboratory in Cheshire – each of which offers a different cluster of technological expertise that underpins and ties together diverse research fields.

    The combination of access to world-class research facilities and scientists, office and laboratory space, business support, and an environment which encourages innovation has proven a compelling combination, attracting start-ups, SMEs and large blue chips such as IBM and Unilever.

    We think our science is awesome – and we know students, teachers and parents think so too. That’s why we run an extensive Public Engagement and science communication programme, ranging from loans to schools of Moon Rocks, funding support for academics to inspire more young people, embedding public engagement in our funded grant programme, and running a series of lectures, travelling exhibitions and visits to our sites across the year.

    Ninety per cent of physics undergraduates say that they were attracted to the course by our sciences, and applications for physics courses are up – despite an overall decline in university enrolment.

     
  • richardmitnick 11:42 am on January 7, 2018 Permalink | Reply
    Tags: , CNRS ANTERES, Do fast radio bursts emit high-energy neutrinos?, , Neutrinos,   

    From IceCube: “Do fast radio bursts emit high-energy neutrinos?” 

    icecube
    U Wisconsin IceCube South Pole Neutrino Observatory

    ICECUBE neutrino detector

    19 Dec 2017
    Sílvia Bravo

    Maybe, but not many, according to IceCube.

    Although fast radio bursts’ (FRBs) progenitors are supposed to be compact and perhaps catastrophic cosmic events that may also produce neutrinos, IceCube has not detected any such neutrinos that could be associated with a known FRB in six years of data. These results are far from precluding the eventual detection of neutrinos from FRBs in the future, but they have set the best limits yet on how many are emitted. The results have been submitted today to The Astrophysical Journal.

    1
    The most signal-like event in both northern searches was detected 200.806 s after the radio detection of FRB 121102 b3. The directional reconstruction of this event has an angular separation ∆Ψ= 2.31◦ with the FRB and an estimated error σ= 1.31◦. Event reconstruction contours are drawn for confidence intervals of 50%, 90%, and 99%, taking the reconstruction as a radially symmetric 2-D Gaussian. FRB directional uncertainty (<<1◦) is taken into account in this analysis, but not shown for this scale. The post-trial p-value for this max-burst search is p=0.25. Image: IceCube Collaboration.

    A fast radio burst consists of bright radio emission, usually only a few milliseconds long, that may be the result of the collision of a neutron star with a black hole or of another extreme astrophysical event. Discovered in 2007, they were initially thought to be produced by a cataclysmic event that would destroy its source. However, ten years after their discovery, at least one of the sources has produced repeated radio bursts over 100 times. According to Justin Vandenbroucke, an assistant professor of physics at UW–Madison and a corresponding author of this work, “fast radio bursts are a mysterious new class of astrophysical transients—we don’t know what’s producing them.”

    Between May 2010 and May 2016, radio astronomers detected 29 FRBs across the whole sky from a total of 13 directions–17 of them were bursts from FRB 121101, the only source to date that has been found to repeat. IceCube’s gigantic size, a cubic kilometer of instrumented ice, provides omnidirectional detection capabilities that enable a continuous scan of both the northern and southern sky. In these six years of data, a few neutrinos were detected near the locations of some FRBs, but scientists have shown that their arrival times and overall distribution can be explained with background neutrino emission from other sources.

    “This is only the beginning of a long quest,” says Donglian Xu, a postdoctoral researcher at UW–Madison and also a corresponding author of this paper.

    FRBs are one of the hottest topics in astrophysics. In the near future, brand new radio observatories may discover over a thousand FRBs every year. And that’s why scientists around the world are honing their analysis skills to use signals from multiple messengers to learn about the origins of these fast, whether one-time or intermittent, radio bursts.

    In IceCube, this search for neutrino emission from FRBs used data samples optimized for searches of neutrinos from gamma-ray bursts (GRBs) with energies between 0.1 TeV and several PeV. IceCube scientists are already working on a more sensitive selection that will include all neutrino flavors and lower the energy threshold. Samuel Fahey, a graduate student at UW–Madison, is one of those scientists. “We’re working on using every tool at IceCube’s disposal—this analysis was just one piece of the puzzle.”

    Very little is known about the sources of FRBs. Their distribution across the sky, as well as indirect evidence of their distance, suggests an extragalactic origin. Yet only one FRB is proven to be extragalactic. Galactic neutron stars or other sources might also produce radio bursts. If this happens, IceCube might detect a sudden increase in the background Cherenkov light due to MeV-scale neutrinos.

    3
    A 2-dimensional plot shows the ratio of the effective areas of IceCube to ANTARES over energy and declination, with a bin-width of 0.1 in sin(δ) and bin-height equal to one quarter of a decade in energy. Where ANTARES provides a non-zero effective area, but IceCube’s is equal to zero for this event selection, the ratio plotted is the scale minimum; likewise, where the converse is true, the ratio plotted is the scale maximum. Image: IceCube Collaboration.

    The most powerful searches can benefit from the collaboration of two telescopes, as is often the case in neutrino astronomy. ANTARES, a smaller neutrino telescope in the Mediterranean Sea, has better sensitivity in the Southern Hemisphere for energies below 50 TeV.

    4
    CNRS ANTERES

    In a joint search for FRBs, IceCube and ANTARES could provide the best sensitivity across the full sky.

    The good news is that, one way or another, neutrinos are ready to roll in the quest for FRBs.

    See the full article here .

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    IceCube is a particle detector at the South Pole that records the interactions of a nearly massless sub-atomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars. The IceCube telescope is a powerful tool to search for dark matter, and could reveal the new physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. IceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice.

     
  • richardmitnick 3:06 pm on January 6, 2018 Permalink | Reply
    Tags: , , , Neutrinos, Neutrinos Suggest Solution to Mystery of Universe’s Existence, , , , T2K Experiment/Super-Kamiokande Collaboration   

    From Quanta: “Neutrinos Suggest Solution to Mystery of Universe’s Existence” 

    Quanta Magazine
    Quanta Magazine

    December 12, 2017
    Katia Moskvitch

    1
    A neutrino passing through the Super-Kamiokande experiment creates a telltale light pattern on the detector walls. T2K Experiment/Super-Kamiokande Collaboration, Institute for Cosmic Ray Research, University of Tokyo

    T2K Experiment, Tokai to Kamioka, Japan

    T2K Experiment, Tokai to Kamioka, Japan

    From above, you might mistake the hole in the ground for a gigantic elevator shaft. Instead, it leads to an experiment that might reveal why matter didn’t disappear in a puff of radiation shortly after the Big Bang.

    I’m at the Japan Proton Accelerator Research Complex, or J-PARC — a remote and well-guarded government facility in Tokai, about an hour’s train ride north of Tokyo.

    J-PARC Facility Japan Proton Accelerator Research Complex , located in Tokai village, Ibaraki prefecture, on the east coast of Japan

    The experiment here, called T2K (for Tokai-to-Kamioka) produces a beam of the subatomic particles called neutrinos. The beam travels through 295 kilometers of rock to the Super-Kamiokande (Super-K) detector, a gigantic pit buried 1 kilometer underground and filled with 50,000 tons (about 13 million gallons) of ultrapure water. During the journey, some of the neutrinos will morph from one “flavor” into another.

    In this ongoing experiment, the first results of which were reported last year, scientists at T2K are studying the way these neutrinos flip in an effort to explain the predominance of matter over antimatter in the universe. During my visit, physicists explained to me that an additional year’s worth of data was in, and that the results are encouraging.

    According to the Standard Model of particle physics, every particle has a mirror-image particle that carries the opposite electrical charge — an antimatter particle.

    Standard Model of Particle Physics from Symmetry Magazine

    When matter and antimatter particles collide, they annihilate in a flash of radiation. Yet scientists believe that the Big Bang should have produced equal amounts of matter and antimatter, which would imply that everything should have vanished fairly quickly. But it didn’t. A very small fraction of the original matter survived and went on to form the known universe.

    Researchers don’t know why. “There must be some particle reactions that happen differently for matter and antimatter,” said Morgan Wascko, a physicist at Imperial College London. Antimatter might decay in a way that differs from how matter decays, for example. If so, it would violate an idea called charge-parity (CP) symmetry, which states that the laws of physics shouldn’t change if matter particles swap places with their antiparticles (charge) while viewed in a mirror (parity). The symmetry holds for most particles, though not all. (The subatomic particles known as quarks violate CP symmetry, but the deviations are so small that they can’t explain why matter so dramatically outnumbers antimatter in the universe.)

    Last year, the T2K collaboration announced the first evidence that neutrinos might break CP symmetry, thus potentially explaining why the universe is filled with matter. “If there is CP violation in the neutrino sector, then this could easily account for the matter-antimatter difference,” said Adrian Bevan, a particle physicist at Queen Mary University of London.

    Researchers check for CP violations by studying differences between the behavior of matter and antimatter. In the case of neutrinos, the T2K scientists explore how neutrinos and antineutrinos oscillate, or change, as the particles make their way to the Super-K detector. In 2016, 32 muon neutrinos changed to electron neutrinos on their way to Super-K. When the researchers sent muon antineutrinos, only four became electron antineutrinos.

    That result got the community excited — although most physicists were quick to point out that with such a small sample size, there was still a 10 percent chance that the difference was merely a random fluctuation. (By comparison, the 2012 Higgs boson discovery had less than a 1-in-1 million probability that the signal was due to chance.)

    This year, researchers collected nearly twice the amount of neutrino data as last year. Super-K captured 89 electron neutrinos, significantly more than the 67 it should have found if there was no CP violation. And the experiment spotted only seven electron antineutrinos, two fewer than expected.

    3
    Lucy Reading-Ikkanda for Quanta Magazine

    Researchers aren’t claiming a discovery just yet. Because there are still so few data points, “there’s still a 1-in-20 chance it’s just a statistical fluke and there isn’t even any violation of CP symmetry,” said Phillip Litchfield, a physicist at Imperial College London. For the results to become truly significant, he added, the experiment needs to get down to about a 3-in-1000 chance, which researchers hope to reach by the mid-2020s.

    But the improvement on last year’s data, while modest, is “in a very interesting direction,” said Tom Browder, a physicist at the University of Hawaii. The hints of new physics haven’t yet gone away, as we might expect them to do if the initial results were due to chance. Results are also trickling in from another experiment, the 810-kilometer-long NOvA at the Fermi National Accelerator Laboratory outside Chicago.

    FNAL/NOvA experiment map

    FNAL NOvA Near Detector

    Last year it released its first set of neutrino data, with antineutrino results expected next summer. And although these first CP-violation results will also not be statistically significant, if the NOvA and T2K experiments agree, “the consistency of all these early hints” will be intriguing, said Mark Messier, a physicist at Indiana University.

    A planned upgrade of the Super-K detector might give the researchers a boost. Next summer, the detector will be drained for the first time in over a decade, then filled again with ultrapure water. This water will be mixed with gadolinium sulfate, a type of salt that should make the instrument much more sensitive to electron antineutrinos. “The gadolinium doping will make the electron antineutrino interaction easily detectable,” said Browder. That is, the salt will help the researchers to separate antineutrino interactions from neutrino interactions, improving their ability to search for CP violations.

    “Right now, we are probably willing to bet that CP is violated in the neutrino sector, but we won’t be shocked if it is not,” said André de Gouvêa, a physicist at Northwestern University. Wascko is a bit more optimistic. “The 2017 T2K result has not yet clarified our understanding of CP violation, but it shows great promise for our ability to measure it precisely in the future,” he said. “And perhaps the future is not as far away as we might have thought last year.”

    See the full article here .

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    Formerly known as Simons Science News, Quanta Magazine is an editorially independent online publication launched by the Simons Foundation to enhance public understanding of science. Why Quanta? Albert Einstein called photons “quanta of light.” Our goal is to “illuminate science.” At Quanta Magazine, scientific accuracy is every bit as important as telling a good story. All of our articles are meticulously researched, reported, edited, copy-edited and fact-checked.

     
  • richardmitnick 4:30 pm on December 19, 2017 Permalink | Reply
    Tags: , , CERN Large Hadron Collider, , , , , Large Electron-Positron Collider, Neutrinos, , , , ,   

    From Symmetry: “Machine evolution” 

    Symmetry Mag
    Symmetry

    12/19/17
    Amanda Solliday

    1
    Courtesy of SLAC

    Planning the next big science machine requires consideration of both the current landscape and the distant future.

    Around the world, there’s an ecosystem of large particle accelerators where physicists gather to study the most intricate details of matter.

    These accelerators are engineering marvels. From planning to construction to operation to retirement, their lifespans stretch across decades.

    But to get the most out of their investments of talent and funding, laboratories planning such huge projects have to think even longer-term: What could these projects become in their next lives?

    The following examples show how some of the world’s big physics machines have evolved to stay at the forefront of science and technology.

    Same tunnel, new collisions

    Before CERN research center in Geneva, Switzerland, had its Large Hadron Collider, it had the Large Electron-Positron Collider. LEP was the largest electron-positron collider ever built, occupying a nearly 17-mile circular tunnel dug beneath the border of Switzerland and France. The tunnel took three years to completely excavate and build.

    The first particle beam traveled around the LEP circular collider in 1989. Long before then, the international group of CERN physicists and engineers were already thinking about what CERN’s next machine could be.

    “People were saying, ‘Well, if we do build LEP, then we should make it compatible with the [then-proposed] Large Hadron Collider,’” says James Gillies, a senior communications advisor and member of the strategic planning and evaluation unit at CERN. “If you want to have a future facility, you often have to engage the people who just finished designing one machine to start thinking about the next one.”

    LEP’s designers chose an energy for the collider that would mass-produce Z bosons, fundamental particles discovered by earlier experiments at CERN. The LHC would be a step up from LEP, reaching higher energies that scientists hoped could produce the Higgs boson. In the 1960s, theorists proposed the Higgs as a way to explain the origin of the mass of elementary particles. And the new machine to look for it could be built in the same 17-mile tunnel excavated for LEP.

    Engineers began working on the LHC while LEP was still running. The new machine required enlargements to underground areas—it needed bigger detectors and new experimental halls.

    “That was challenging because these caverns are huge. As they were being excavated, the pressure on the LEP tunnel was reduced and the LEP beamline needed realignment,” Gillies says. “So you constantly had to realign the collider for experiments as you were digging.”

    After LEP reached its highest energy in 2000, it was switched off. The tunnel remained the same, says Gillies, but there were many other changes. Only one of the LEP detectors, DELPHI, remains underground at CERN as a visitors’ point.

    In 2012, LHC scientists announced the discovery of the long-sought Higgs boson. The LHC is planned to continue running until at least 2035, gradually increasing the intensity of its particle collisions. The research and development into the accelerator’s successor is already happening. The possibilities include a higher energy LHC, a compact linear collider or an even larger circular collider.

    2

    Large Electron-Positron Collider
    Location: CERN—Geneva, Switzerland
    First beam: 1989
    Link to LEP Timeline: Timeline
    Courtesy of CERN

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    Large Hadron Collider
    Location: CERN—Geneva, Switzerland
    First beam: 2008
    Link to LHC Timeline: Timeline
    Courtesy of CERN

    High-powered science
    Decades before the LHC came into existence, a suburb of Chicago was home to the most powerful collider in the world: the Tevatron. A series of accelerators at Fermi National Accelerator Laboratory boosted protons and antiprotons to nearly the speed of light. In the final, 4-mile Tevatron ring, the particles reached record energy levels, and more than 1000 superconducting magnets steered them into collisions. Physicists used the Tevatron to make the first direct measurement of the tau neutrino and to discover the top quark, the last observed lepton and quark, respectively, in the Standard Model.

    The Tevatron shut down in 2011 after the LHC came up to speed, but the rest of Fermilab’s accelerator infrastructure was still hard at work powering research in particle physics—particularly on the abundant, mysterious and difficult-to-detect neutrino.

    Starting in 1999, a brand-new, 2-mile circular accelerator called the Main Injector was added to the Fermilab complex to increase the number of Tevatron particle collisions tenfold. It was joined in its tunnel by the Recycler, a permanent magnet ring that stored and cooled antiprotons.

    But before the Main Injector was even completed, scientists had identified a second purpose: producing powerful beams of neutrinos for experiments in Illinois and 500 miles away in Minnesota.

    FNAL/NOvA experiment map

    By 2005, the proton beam circulating in the Main Injector was doing double duty: sending ever-more-intense beams to the Tevatron collider and smashing into a target to produce neutrinos. Following the shutdown of the Tevatron, the Recycler itself was recycled to increase the proton beam power for neutrino research.

    “I’m still amazed at how we are able to use the Recycler. It can be difficult to transition if a machine wasn’t originally built for that purpose,” says Ioanis Kourbanis, the head of the Main Injector department at Fermilab.

    Fermilab’s high-energy neutrino beam is already the most intense in the world, but the laboratory plans to enhance it with future improvements to the Main Injector and the Recycler, and to build a brand-new neutrino beamline.

    Neutrinos almost never interact with matter, so they can pass straight through the Earth on their way to detectors onsite and others several hundred miles away. Scientists hope to learn more about neutrinos and their possible role in shaping our early universe.

    The new beamline will be part of the Long-Baseline Neutrino Facility, which will send neutrinos 800 miles underground to the massive, mile-deep detectors of the Deep Underground Neutrino Experiment.

    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

    Scientists from around the world will use the DUNE data to answer questions about neutrinos, thanks to the repurposed pieces of the Fermilab accelerator complex.

    5

    FNAL Tevatron

    FNAL/Tevatron map


    FNAL/Tevatron DZero detector


    FNAL/Tevatron CDF detector

    Tevatron
    Location: Fermilab—Batavia, Illinois
    First beam: 1983
    Link to Tevatron Timeline: Timeline
    Courtesy of Fermilab

    6

    Neutrinos at the Main Injector (NuMI) beam
    Location: Fermilab—Batavia, Illinois
    First beam: 2004
    Link to Fermilab Timeline: Timeline
    Courtesy of Fermilab

    A monster accelerator

    When physicists first came up with the idea to build a two-mile linear accelerator at what is now called SLAC National Accelerator Laboratory, managed by Stanford University, they called it “Project M” for “Monster.” Engineers began building it from hand-drawn designs. Once completed, the machine was able to accelerate electrons to near the speed of light, producing its first particle beam in May 1966.

    SLAC Campus

    The accelerator’s scientific purpose has gone through several iterations of particle physics experiments over the decades, from fixed-target experiments to the Stanford Linear Collider (the only electron-positron linear collider ever built) to an injector for a circular collider, the Positron-Electron Project.

    These experiments led to the discovery that protons are made of quarks, the first evidence that the charm quark existed (through observations of the J/psi particle, co-discovered with researchers at MIT) and the discovery of the tau lepton.

    In 2009, the lab used the accelerator as the backbone for a different type of science machine—an X-ray free-electron laser, the Linac Coherent Light Source.

    “Looking around, SLAC was the only place in the world with a linear accelerator capable of driving a free-electron laser,” says Claudio Pellegrini, a distinguished professor emeritus of physics at the University of California, Los Angeles and a visiting scientist and consulting professor at SLAC. Pellegrini first proposed the idea to transform SLAC’s linear accelerator.

    The new machine, a DOE Office of Science user facility, would be the world’s first laser of its kind that could produce extremely bright hard X-rays, the high-energy X-rays that let scientists take snapshots of atoms and molecules.

    “Much of the physics and many of the tools learned and developed during the operation of the Stanford Linear Collider were directly applicable to the free electron laser,” says Lia Merminga, head of the accelerator directorate at SLAC. “This was a big factor in the LCLS being commissioned in record time. Without the Stanford Linear Collider experience, this significant body of work would have to be reinvented and reproduced almost from scratch.”

    Little about the accelerator itself needed to change. But to create a free-electron laser, scientists needed to design a new part: an electron gun, a device that generates electrons to be injected into the accelerator. A collaboration of several national labs and UCLA created a new type of electron gun for LCLS, while other national labs helped build undulators, a series of magnets that would wiggle the electrons to create X-rays.

    LCLS used only the last third of SLAC’s original linear accelerator. In part of the remaining section, scientists are developing plasma wakefield and other new particle acceleration techniques.

    For the X-ray laser’s next iteration, LCLS-II, scientists are aiming for an even brighter laser that will fire 1 million pulses per second, allowing them to observe rare and exceptionally transient events.

    SLAC/LCLS II

    To do this, they will need to replace the original copper structures with superconducting technology. The technology is derived from designs for a large International Linear Collider [ILC] proposed to be built in Japan.

    ILC schematic

    “I’m in awe of the foresight of the original builders of SLAC’s linear accelerator,” Merminga adds. “We’ve been able to do so much with this machine, and the end is not yet in sight.”

    7

    Fixed target and collider experiments

    Location: SLAC—Menlo Park, California
    First beam: 1966
    Link to SLAC Timeline: Timeline
    Courtesy of SLAC

    8

    Linac Coherent Light Source
    Location: SLAC—Menlo Park, California
    First beam: 2009
    Link to SLAC Timeline: Timeline
    Courtesy of SLAC

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 1:49 pm on November 28, 2017 Permalink | Reply
    Tags: , , Neutrinos, , The Ross Shaft   

    From SURF: “The Ross Shaft” 

    SURF logo
    Sanford Underground levels

    Sanford Underground Research facility

    11.28.17
    Constance Walter
    Communications Director
    Office: 605.722.4025 • Mobile: 402-560-6116
    Sanford Underground Research Facility
    630 E. Summit St. Lead, SD 57754
    http://www.sanfordlab.org

    1

    Historical sources for this article include Steve Mitchell’s Nuggets to Neutrinos

    Historical images were provided by Black Hills Mining Museum

    Other information provided by Fermi National Accelerator Laboratory [FNAL]

    Reaching the 4850 Level is a major milestone that moves the team—and science—one step closer to a larger goal.

    For more than five years, Ross Shaft crews have been stripping out old steel and lacing, cleaning out decades of debris, adding new ground support and installing new steel to prepare the shaft for its future role in world-leading science. On Oct. 12, all that hard work paid off when the team, which worked its way down from the surface, reached a major milestone: the 4850 Level.

    “As we got closer to the station and we could see the lights off the 4850, there was a lot of excitement from the crew,” said Mike Johnson, Ross Shaft foreman. “It was like, ‘Man, we’re finally here.’”

    Mike Headley, executive director for the South Dakota Science and Technology Authority, praised the Ross Shaft team. “The Ross Shaft is critical to the future of Sanford Lab and I am incredibly proud of the hard work and dedication shown by this team.”

    Refurbishing the shaft is just one step toward a much larger goal, said Chris Mossey, Fermilab’s deputy director for LBNF.

    “Completion of the Ross Shaft renovation to the 4850 Level is critical to support construction of the Long-Baseline Neutrino Facility [LBNF]. Thanks to the Sanford Lab crews, who have worked since August 2012, to reach this significant milestone.”

    3
    A team effort. On Oct. 12, 2017, the team reached a major milestone by finishing the Ross Shaft down to the 4850-foot level. Pictured from left: Ross foreman Mike L. Johnson, infrastructure technicians Rodney Hanson, Dan James, Jerry Hinker, Dave Leatherman, Derek Lucero, Frank Gabel, Mike Mergen, Eli Atkinson, Clint Morrison, James Gregory, Will Roberts, Curtis Jones, engineering technician Kip Johnson, and infrastructure technician Kyle Ennis.

    LBNF will house the international Deep Underground Neutrino Experiment (DUNE), which will be built and operated by a collaboration of more than 1,000 scientists and engineers from 31 countries.

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


    FNAL DUNE Argon tank at SURF


    Surf-Dune/LBNF Caverns at Sanford

    Fermilab will shoot a beam of neutrinos 800 miles through the earth from Fermilab to massive particle detectors deep underground at Sanford Lab’s 4850 Level.

    When complete, the Fermilab-hosted LBNF/DUNE project will be the largest experiment ever built in the United States to study the properties of mysterious particles called neutrinos. Unlocking the mysteries of these particles could help explain more about how the universe works and why matter exists at all.

    But before scientists begin installing the DUNE detectors, the shaft needs to be completed to the 5000-foot level and a rock conveyor system installed to excavate the caverns that will house DUNE. Still, there’s much to celebrate.

    “This is a great accomplishment,” Johnson said. “We’ve got a team with different experiences and talents and they really worked together to reach this milestone.” But Johnson said credit goes to a lot people who have never set foot in the shaft.

    “Engineers, fabricators, vendors, electricians, procurement—everyone played a part in getting us to this point,” he said. “It takes a lot of planning and support. It was a real team effort.

    4
    A historic shaft
    The Ross Shaft was named for Homestake Superintendent Alec J. M. Ross. Construction began in 1932, with the first ore hoisted in 1934. The shaft used conventional sinking methods from 137 feet down to the tramway level. Below the tramway, pilot raises were driven at various depths to complete the shaft down to the 3050 Level. The Ross was deepened to nearly 3,800 feet in 1935 but wouldn’t reach the 5000 Level until the end of 1956.
    The Ross Shaft was designed to meet production requirements for Homestake, when the Ellison, the main production shaft, began to suffer from subsidence. The new shaft was closer to the south-plunging ore body, providing access to an additional 6.5 million tons of ore in an area known as 9 Ledge. The ore averaged 0.269 ounces of gold per ton. In 1938, the average price for an ounce of gold was $20.67.

    5
    Built for production
    The Ross Shaft is 19 feet 3 inches by 14 feet and is divided into several compartments: two skips, a cage, a counter weight, a cable compartment, a pipe compartment and an access compartment (called a manway during mining days). Two sections of the shaft were lined with concrete for added ground support: the first 308 feet of the shaft and a section between the 2900 and 4100 levels.
    Homestake built the shaft using steel sets spaced 6 feet apart. The “H” beam configuration served the purpose of gold mining very well, said Syd De Vries, project engineer for the current Ross Shaft project.
    For nearly 70 years, the Ross Shaft served as a main conduit for thousands of miners and millions of tons of ore. But debris, water and time took their toll on the structure. When the facility reopened as an underground research laboratory in 2008, the structure needed to be replaced to meet the needs of science.

    6
    The SDSTA called on G.L. Tiley and Associates to develop a design that could meet the new requirements for world-leading science. De Vries coordinated the design efforts.
    “We looked at options that included partial refurbishment. In the end, we concluded that a complete strip and equip was the right approach to take,” De Vries said. That included a more modern design that incorporated the use of hollow structural steel with set intervals of 18 feet.
    “Essentially, using these larger sets speeds up the process of steel refurbishment. But it also gives us a much stronger design than the old-style steel sets and improves the structural integrity of the shaft,” De Vries added.
    Above: Old steel sets at the 300 Level station. Note: near the top of the station, a new steel set is visible.

    7
    Two parts of the project required specialized structural design after the rehabilitation had begun to accommodate LBNF. Those areas include the brow at the 4850 Level and the spill collection area on the 5000 Level. De Vries worked closely with G.L. Tiley on the new designs—and sought the expertise of the crews on installation plans.
    “I’ve always found that when we do that, when we incorporate the expertise the crews have with respect to steel construction, we can work out any challenge and do a much better job.”
    And even with the changes in structural design, De Vries said it won’t hold up the project.
    Above: New steel at the 2000 Level station. Watch a short time-lapse of the completion of the 800 Level station below.

    800 Level station rehabilitation time lapse from Sanford Lab on Vimeo.

    8
    Meeting challenges
    The Ross Shaft is a unique construction project that included a unique set of challenges. Of particular concern? A design that allowed continued access to critical systems like the pumping stations and ventilation, while providing emergency egress.
    “From a construction point of view, it would have been easier and faster if we didn’t have to worry about ongoing access,” De Vries said. “We wouldn’t have had to shut down for shaft inspections of the lower sections or pump stations.”
    Another challenge was the Ross Pillar, a 1,200-foot concrete zone within the shaft used as additional ground support during mining days. Over the years, normal ground movement caused misalignment from the 2900 Level to the 4100 Level. In some areas, the encroaching concrete bowed the steel, making it difficult to move the cage through the shaft.
    “There was a lot of work that went into redoing this section and creating more room for the conveyances,” De Vries said. “In some places, the crews had to chip out the concrete liner with chipping hammers. They did a great job and I’m really proud of the work that was done.”
    Above: Looking down the Ross Shaft where a new set meets an old set.

    9
    Safety first
    Throughout construction of the Ross Shaft, safety has been of the utmost concern, said Johnson. “This is hard work with a lot of challenges, so safety is a big deal.”
    To mitigate risks, the team uses Job Hazard Analyses (JHAs) and follows Standard Operating Procedures (SOPs). The team starts its day with a tool-box talk. They go through the JHAs step by step and make sure they have everything they need to do the job safely.
    Recently Johnson incorporated a “mid-shift” safety talk, something he used while working in the oil fields in North Dakota. “Things can change throughout the day, so we talk about the job mid-shift to see if we need to make any adjustments.”
    “You know, we’ve got our families at home and our family at work. Taking this extra step takes time, but if it keeps people safe, it’s worth it,” Johnson said.
    Above: Technicians install ground support in the Ross Shaft.

    The future

    On Aug. 9, 2007 Fermi Research Alliance LLC, which operates Fermilab, awarded Kiewit/Alberici Joint Venture (KAJV) a contract to begin laying the groundwork for the excavation of LBNF, the facility that will support DUNE.

    Approximately 875,000 tons of rock will be removed and conveyed to the surface, then moved to the Open Cut using a rock conveyor system. When installation of LBNF and DUNE equipment begins, every component, including the massive steel beams that will be used to build the cryostats, will go down the Ross Shaft.

    “It’s kind of like building a ship in a bottle,” said Fermilab’s Chris Mossey. “We’re using a narrow shaft to move all the excavated rock up, and then all the parts and pieces of the very large cryostats and detectors for DUNE down to the 4850 level, about a mile underground.”

    Construction on pre-excavation projects, including additional work on the brow at the 4850 Level and the rock conveyor system, is expected to begin in 2018. The main excavation for LBNF/DUNE is planned for 2019 and is expected to take three years.

    Installation of the cryogenic infrastructure and the four detector modules for the experiment is expected to take about 10 years and will operate for more than 20 years. The Ross Shaft will play a role throughout, just as it did for many decades when Homestake mined for gold.

    “Now it has a new purpose,” said Sanford Lab’s Headley. “It will support world-leading science for decades to come.”

    See the full article here .

    Please help promote STEM in your local schools.
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    About us.
    The Sanford Underground Research Facility in Lead, South Dakota, advances our understanding of the universe by providing laboratory space deep underground, where sensitive physics experiments can be shielded from cosmic radiation. Researchers at the Sanford Lab explore some of the most challenging questions facing 21st century physics, such as the origin of matter, the nature of dark matter and the properties of neutrinos. The facility also hosts experiments in other disciplines—including geology, biology and engineering.

    The Sanford Lab is located at the former Homestake gold mine, which was a physics landmark long before being converted into a dedicated science facility. Nuclear chemist Ray Davis earned a share of the Nobel Prize for Physics in 2002 for a solar neutrino experiment he installed 4,850 feet underground in the mine.

    Homestake closed in 2003, but the company donated the property to South Dakota in 2006 for use as an underground laboratory. That same year, philanthropist T. Denny Sanford donated $70 million to the project. The South Dakota Legislature also created the South Dakota Science and Technology Authority to operate the lab. The state Legislature has committed more than $40 million in state funds to the project, and South Dakota also obtained a $10 million Community Development Block Grant to help rehabilitate the facility.

    In 2007, after the National Science Foundation named Homestake as the preferred site for a proposed national Deep Underground Science and Engineering Laboratory (DUSEL), the South Dakota Science and Technology Authority (SDSTA) began reopening the former gold mine.

    In December 2010, the National Science Board decided not to fund further design of DUSEL. However, in 2011 the Department of Energy, through the Lawrence Berkeley National Laboratory, agreed to support ongoing science operations at Sanford Lab, while investigating how to use the underground research facility for other longer-term experiments. The SDSTA, which owns Sanford Lab, continues to operate the facility under that agreement with Berkeley Lab.

    The first two major physics experiments at the Sanford Lab are 4,850 feet underground in an area called the Davis Campus, named for the late Ray Davis. The Large Underground Xenon (LUX) experiment is housed in the same cavern excavated for Ray Davis’s experiment in the 1960s.
    LUX/Dark matter experiment at SURFLUX/Dark matter experiment at SURF

    In October 2013, after an initial run of 80 days, LUX was determined to be the most sensitive detector yet to search for dark matter—a mysterious, yet-to-be-detected substance thought to be the most prevalent matter in the universe. The Majorana Demonstrator experiment, also on the 4850 Level, is searching for a rare phenomenon called “neutrinoless double-beta decay” that could reveal whether subatomic particles called neutrinos can be their own antiparticle. Detection of neutrinoless double-beta decay could help determine why matter prevailed over antimatter. The Majorana Demonstrator experiment is adjacent to the original Davis cavern.

    Another major experiment, the Long Baseline Neutrino Experiment (LBNE)—a collaboration with Fermi National Accelerator Laboratory (Fermilab) and Sanford Lab, is in the preliminary design stages. The project got a major boost last year when Congress approved and the president signed an Omnibus Appropriations bill that will fund LBNE operations through FY 2014. Called the “next frontier of particle physics,” LBNE will follow neutrinos as they travel 800 miles through the earth, from FermiLab in Batavia, Ill., to Sanford Lab.

    Fermilab LBNE
    LBNE

     
  • richardmitnick 7:51 pm on November 22, 2017 Permalink | Reply
    Tags: , , Neutrinos, , Sandra Miarecki, ,   

    From LBNL: Women in STEM- “A Flight Path to Physics Success” Sandra Miarecki 

    Berkeley Logo

    Berkeley Lab

    November 22, 2017
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 520-0843

    3
    Sandra Miarecki

    1
    In a previous career, Sandra Miarecki flew high above the Earth’s surface. During a 20-year career in the U.S. Air Force that included time as a test pilot, she flew aircraft including the B-52, F-16, MiG-15, helicopters, and even the Goodyear Blimp.

    2
    Sandra Miarecki boards a T-38 Talon aircraft during her time as a U.S. Air Force pilot. (Photo courtesy of Sandra Miarecki)

    She retired from the Air Force in 2007 to pursue a new calling in physics that would set her sights on the depths of the Earth. Now an assistant professor of physics, Miarecki served as the principal researcher in a just-released study that relied on data from a detector encapsulated in ice near the South Pole to determine how high-energy subatomic particles are absorbed as they travel inside the planet.

    It was a chance seat assignment on a passenger jet in 2007 that put her next to Robert Stokstad, a Lawrence Berkeley National Laboratory (Berkeley Lab) physicist who was then serving as the project director for the Lab’s IceCube Neutrino Observatory team.


    U Wisconsin ICECUBE neutrino detector at the South Pole

    Miarecki was on a scouting trip to find housing in the San Francisco Bay Area in preparation for her pursuit of a Ph.D. at UC Berkeley.

    “He was playing with a camera, and I was involved with photography,” she recalled of the chance meeting on that Southwest Airlines flight, and they struck up a conversation. The subject of science came up, and his description of the IceCube project, then under construction, piqued her interest.

    She would later attend a Berkeley Lab IceCube group meeting at Stokstad’s invitation. “I thought I was going to be a cosmology theorist when I first got to Berkeley,” she said, but hands-on experiments were also alluring.

    So she worked on a summer project with the collaboration, and enjoyed the experience.

    Spencer Klein, a longtime physicist at Berkeley Lab who now leads the Lab’s IceCube team, suggested that Miarecki’s dissertation focus on the Earth’s absorption of high-energy neutrinos. Before joining the Air Force, Miarecki had earned a bachelor’s degree in astronomy, and also completed courses in physics and mathematics, at the University of Illinois at Urbana-Champaign.

    “I had also toyed with the idea of being a geologist, and when you are using the Earth as an absorption material (for neutrinos), you have to understand the composition and density of the Earth. It was a really nice blend of all my previous experience,” she said. “I was so happy when we came up with this idea.”

    Miarecki worked full-time on this research at Berkeley Lab from 2010 to 2015 before taking a job in January 2016 as a physics instructor at the Air Force Academy in Colorado Springs, Colorado. She continued working on her dissertation at the academy, completing that work in December 2016.

    When Klein suggested that she submit her dissertation work for publication in Nature, a high-profile science journal, Miarecki balked at first. “I said, ‘Really?’ Then I thought, ‘OK, let’s give it a try,’” she said. “It’s not expected that your graduate dissertation actually gets into Nature.” The study was published on Nov. 22.

    She was promoted to assistant professor at the academy in January 2017, and now teaches physics coursework in classical mechanics and electromagnetism as well as the physics of combat aviation.

    “When I was going through the military retirement transition course, the attendees had to answer the question, ‘What do you want to be when you grow up,’ which was tongue-in-cheek, of course, because all of us were over 40,” Miarecki recalled. “I realized that I wanted to teach, and I had always been told that I was a great teacher. The military also had selected me to be an instructor pilot at several times during my career.”

    She added, “I debated whether my 42-year-old brain would be spongy enough to tackle a Ph.D. program, but I decided that I had to try, or I could never live with myself wondering, ‘What could have been?’ Switching from the military to academia was not a big shock because I had spent so much of my military career in a teaching capacity.”

    The assistant professor position at the Air Force Academy has brought her career full circle, she noted: “It represents a perfect blend of my previous Air Force career with my love of teaching physics.”

    See the full article here .

    Please help promote STEM in your local schools.

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

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