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  • richardmitnick 12:21 pm on July 16, 2019 Permalink | Reply
    Tags: , being replaced by LBNL Lux Zeplin project, , ending, , Lead, , , SD, , U Washington LUX Dark matter Experiment at SURF, , WIMPs-weakly interacting massive particles   

    From Lawrence Berkeley National Lab: “Some Assembly Required: Scientists Piece Together the Largest U.S.-Based Dark Matter Experiment” 

    Berkeley Logo

    From Lawrence Berkeley National Lab

    July 16, 2019

    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 486-5582

    Major deliveries in June set the stage for the next phase of work on LUX-ZEPLIN project.

    1
    Lower (left) and upper photomultiplier tube arrays are prepared for LZ at the Sanford Underground Research Facility in Lead, South Dakota. (Credit: Matt Kapust/SURF)

    Most of the remaining components needed to fully assemble an underground dark matter-search experiment called LUX-ZEPLIN (LZ) arrived at the project’s South Dakota home during a rush of deliveries in June.

    When complete, LZ will be the largest, most sensitive U.S.-based experiment yet that is designed to directly detect dark matter particles. Scientists around the world have been trying for decades to solve the mystery of dark matter, which makes up about 85 percent of all matter in the universe though we have so far only detected it indirectly through observed gravitational effects.

    The bulk of the digital components for LZ’s electronics system, which is designed to transmit and record signals from ever-slight particle interactions in LZ’s core detector vessel, were among the new arrivals at the Sanford Underground Research Facility (SURF). SURF, the site of a former gold mine now dedicated to a broad spectrum of scientific research, was also home to a predecessor search experiment called LUX.

    U Washington LUX Dark matter Experiment at SURF, Lead, SD, USA

    A final set of snugly fitting acrylic vessels, which will be filled with a special liquid designed to identify false dark matter signals in LZ’s inner detector, also arrived at SURF in June.

    3
    An intricately thin wire grid is visible (click image to view larger size) atop an array of photomultiplier tube. The components are part of the LZ inner detector. (Credit: Matt Kapust/SURF)

    Also, the last two of four intricately woven wire grids that are essential to maintain a constant electric field and extract signals from the experiment’s inner detector, also called the time projection chamber, arrived in June (see related article).

    LZ achieved major milestones in June. It was the busiest single month for delivering things to SURF — it was the peak,” said LZ Project Director Murdock Gilchriese of the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). Berkeley Lab is the lead institution for the LZ project, which is supported by an international collaboration that has about 37 participating institutions and about 250 researchers and technical support crew members.

    “A few months from now all of the action on LZ is going to be at SURF — we are already getting close to having everything there,” Gilchriese said.

    Mike Headley, executive director at SURF, said, “We’ve been collectively preparing for these deliveries for some time and everything has gone very well. It’s been exciting to see the experiment assembly work progress and we look forward to lowering the assembled detector a mile underground for installation.”

    4
    Components for the LUX-ZEPLIN project are stored inside a water tank nearly a mile below ground. The inner detector will be installed on the central mount pictured here, and acrylic vessels (wrapped in white) will fit snugly around this inner detector. (Credit: Matt Kapust/SURF)

    All of these components will be transported down a shaft and installed in a nearly mile-deep research cavern. The rock above provides a natural shield against much of the constant bombardment of particles raining down on the planet’s surface that produce unwanted “noise.”

    LZ components have also been painstakingly tested and selected to ensure that the materials they are made of do not themselves interfere with particle signals that researchers are trying to tease out.

    LZ is particularly focused on finding a type of theoretical particle called a weakly interacting massive particle or WIMP by triggering a unique sequence of light and electrical signals in a tank filled with 10 metric tons of highly purified liquid xenon, which is among Earth’s rarest elements. The properties of xenon atoms allow them to produce light in certain particle interactions.

    Proof of dark matter particles would fundamentally change our understanding of the makeup of the universe, as our current Standard Model of Physics does not account for their existence.

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

    Assembly of the liquid xenon time projection chamber for LZ is now about 80 percent complete, Gilchriese said. When fully assembled later this month this inner detector will contain about 500 photomultiplier tubes. The tubes are designed to amplify and transmit signals produced within the chamber.

    5
    An array of photomultiplier tubes that are designed to detect signals occurring within LZ’s liquid xenon tank. (Credit: Matt Kapust/SURF)

    Once assembled, the time projection chamber will be lowered carefully into a custom titanium vessel already at SURF. Before it is filled with xenon, this chamber will be lowered to a depth of about 4,850 feet. It will be carried in a frame that is specially designed to minimize vibrations, and then floated into the experimental cavern across a temporarily assembled metal runway on air-pumped pucks known as air skates.

    Finally, it will be lowered into a larger outer titanium vessel, already underground, to form the final vacuum-insulated cryostat needed to house the liquid xenon.

    That daylong journey, planned in September, will be a nail-biting experience for the entire project team, noted Berkeley Lab’s Simon Fiorucci, LZ deputy project manager.

    “It will certainly be the most stressful — this is the thing that really cannot fail. Once we’re done with this, a lot of our risk disappears and a lot of our planning becomes easier,” he said, adding, “This will be the biggest milestone that’s left besides having liquid xenon in the detector.”

    Project crews will soon begin testing the xenon circulation system, already installed underground, that will continually circulate xenon through the inner detector, further purify it, and reliquify it. Fiorucci said researchers will use about 250 pounds of xenon for these early tests.

    Work is also nearing completion on LZ’s cryogenic cooling system that is required to convert xenon gas to its liquid form.

    6
    Researchers from the University of Rochester in June installed six racks of electronics hardware that will be used to process signals from the LZ experiment. (Credit: University of Rochester)

    LZ digital electronics, which will ultimately connect to the arrays of photomultiplier tubes and enable the readout of signals from particle interactions, were designed, developed, delivered, and installed by University of Rochester researchers and technical staff at SURF in June.

    “All of our electronics have been designed specifically for LZ with the goal of maximizing our sensitivity for the smallest possible signals,” said Frank Wolfs, a professor of physics and astronomy at the University of Rochester who is overseeing the university’s efforts.

    He noted that more than 28 miles of coaxial cable will connect the photomultiplier tubes and their amplifying electronics – which are undergoing tests at UC Davis – to the digitizing electronics. “The successful installation of the digital electronics and the online network and computing infrastructure in June makes us eager to see the first signals emerge from LZ,” Wolfs added.

    Also in June, LZ participants exercised high-speed data connections from the site of the experiment to the surface level at SURF and then to Berkeley Lab. Data captured by the detectors’ electronics will ultimately be transferred to LZ’s primary data center, the National Energy Research Scientific Computing Center (NERSC) at Berkeley Lab via the Energy Sciences Network (ESnet), a high-speed nationwide data network based at Berkeley Lab.

    NERSC

    NERSC Cray Cori II supercomputer at NERSC at LBNL, named after Gerty Cori, the first American woman to win a Nobel Prize in science

    NERSC Hopper Cray XE6 supercomputer


    LBL NERSC Cray XC30 Edison supercomputer


    The Genepool system is a cluster dedicated to the DOE Joint Genome Institute’s computing needs. Denovo is a smaller test system for Genepool that is primarily used by NERSC staff to test new system configurations and software.

    NERSC PDSF


    PDSF is a networked distributed computing cluster designed primarily to meet the detector simulation and data analysis requirements of physics, astrophysics and nuclear science collaborations.

    Future:

    Cray Shasta Perlmutter SC18 AMD Epyc Nvidia pre-exascale supeercomputer

    NERSC is a DOE Office of Science User Facility.

    The production of the custom acrylic tanks (see related article), which will contain a fluid known as a liquid scintillator, was overseen by LZ participants at University of California,Santa Barbara.

    5
    The top three acrylic tanks for the LUX-ZEPLIN outer detector during testing at the fabrication vendor. These tanks are now at the Sanford Underground Research Facility in Lead, South Dakota. (Credit: LZ Collaboration)

    “The partnership between LZ and SURF is tremendous, as evidenced by the success of the assembly work to date,” Headley said. “We’re proud to be a part of the LZ team and host this world-leading experiment in South Dakota.”

    NERSC and ESnet are DOE Office of Science User Facilities.

    Major support for LZ comes from the DOE Office of Science, the South Dakota Science and Technology Authority, the U.K.’s Science & Technology Facilities Council, and by collaboration members in the U.S., U.K., South Korea, and Portugal.

    More:

    For information about LZ and the LZ collaboration, visit: http://lz.lbl.gov/

    See the full article here .

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    LBNL campus

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

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

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

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

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  • richardmitnick 10:43 am on November 14, 2018 Permalink | Reply
    Tags: , , , , , The search for Dark Matter, , WIMPs-weakly interacting massive particles   

    From Sanford Underground Research Facility: “Success of experiment requires testing” 

    SURF logo
    Sanford Underground levels

    From Sanford Underground Research Facility

    November 13, 2018
    Erin Broberg

    1
    Tomasz Biesiadzinski, project scientist for SLAC National Accelerator Laboratory (SLAC), works on the mock PMT [photomultiplier tubes] array. Erin Broberg

    “The LZ detector is kind of like a spacecraft,” said Tomasz Biesiadzinski, project scientist for SLAC National Accelerator Laboratory (SLAC). “Repairing it after it’s installed would be very difficult, so we do everything we can to make sure it works correctly the first time.”

    LZ Dark Matter Experiment at SURF lab

    LBNL LZ project at SURF, Lead, SD, USA

    Biesiadzinski himself is responsible for planning and carrying out tests during the assembly of time projection chamber (TPC), the main detector for LUX-ZEPLIN experiment (LZ). Currently being constructed on the 4850 Level at Sanford Underground Research Facility (Sanford Lab), this main detector consists of a large tank that will hold 7 tonnes of ultra-pure, cryogenic liquid xenon maintained at -100o C. All the pieces of this detector are designed to function with precision; it’s Biesiadzinski job to verify that each part continues to work correctly as they are integrated. That includes hundreds of photomultiplier tubes (PMT).

    Test run

    The most recent test was piecing together an intricate mock array for the PMTs, which will detect light signals created by the collision of a dark matter particle and a xenon atom, inside the main detector. In a soft-wall cleanroom in the Surface Laboratory at Sanford Lab, Biesiadzinski and his team carefully practiced placing instruments like thermometers, sensors and reflective covering. They practiced installing routing cabling, including PMT high voltage power cables, PMT signal cables and thermometer cables.

    “Essentially, we wanted to gain experience so we could be faster during the actual assembly. The faster we work, the more we limit dust exposure and therefore potential backgrounds,” said Biesiadzinski. “It was also an opportunity to test fit real components. We did find that there were some very tight places that motivated us to slightly redesign some small parts to make assembly easier.”

    These tests will make the installment of the actual LZ arrays much smoother.

    “LZ’s main detector will have two PMT arrays, one on the top of the tank and one on the bottom,” Biesiadzinski explained. “The bottom array will hold 241 PMTs pointing up into the liquid Xenon volume of the main detector. The top array will hold PMTs 253 pointing down on the liquid Xenon and the gas layer above it in the main detector.”

    In total, there will be 494 PMTs lining the main detector. If a WIMP streaks through the tank and strikes a xenon nucleus, two things will happen. First, the xenon will emit a flash of light. Then, it will release electrons, which drift in an electric field to the top of the tank, where they will produce a second flash of light. Hundreds of PMTs will be waiting to detect a characteristic combination of flashes from inside the tank—a WIMPs’ telltale signature.

    “Both arrays—top and bottom—record the light from particle interactions inside the detector, including, hopefully, dark matter,” said Biesiadzinski. “This data allows us to estimate both the energy created and 3D location of the interaction.”

    Catching light

    The PMTs used for LZ are extremely sensitive. Not only can they distinguish individual photons of light arriving just a few tens of nanoseconds apart, they can also see the UV light produced by xenon that is far outside the human vision range. The X-Y location of events in the detector can be measured using the top PMT array to within a few millimeters for sufficiently energetic events.

    To insure every bit of light makes its way to a PMT, the inside surfaces of the arrays are covered with Polytetrafluoroethylene (PTFE or teflon), a material highly reflective to xenon scintillation light, in between the PMT faces.

    “This way, photons that don’t enter the PMTs right away—and are therefore not recorded—are reflected and will get a second, third, and so on, chance of being detected as they bounce around the detector,” said Biesiadzinski.

    Researchers will also cover the outside of the bottom array, including all of the cables, with PTFE to maximize light collection there. Light recorded there by additional PMTs that are not part of the array, allow us to measure radioactive backgrounds that can contaminate the main detector.

    Keeping it “clean”

    In addition to being very specific, these PMTs are also ultra-clean.

    “By clean, we mean radio-pure,” said Briana Mount, director of the BHUC, where 338 of LZ’s PMTs have already been tested for radio-purity.

    The tiniest amounts of radioactive elements in the very materials used to construct LZ can also overwhelm the rare-event signal. Radioactive elements can be found in rocks, titanium—even human sweat. As these elements decay, they emit signals that quickly light up ultra-sensitive detectors. To lessen these misleading signatures, researchers assay, or test, their materials for radio-purity using low-background counters (LBCs).

    “Our PMTs are special made to have very low radioactivity so as to not overwhelm a very sensitive detector like LZ with background signal,” said Biesiadzinski.

    Testing the PMTs at the BHUC allows researchers to understand exactly how much of a remaining background they can expect to see from these materials during the experiment. Mount explained that most of the samples currently being assayed at the BHUC are LZ samples, including cable ties, wires, nuts and bolts.

    “We have assayed every component that will make up LZ,” said Kevin Lesko, senior physicist at Lawrence Berkeley National Lab (Berkeley Lab) and a spokesperson for LZ. “At this point we have performed over 1300 assays with another 800 assays planned. These have kept BHUC and the UK’s Boulby LBCs fully occupied for approximately 4 years. These assays permit us ensure no component contributes a major background to the detector and also allows us to assemble a model of the backgrounds for the entire detector before we turn on a single PMT.”

    For a visual description and breakdown of LZ’s design, watch this video created by SLAC.

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster.

    Fritz Zwicky from http:// palomarskies.blogspot.com

    Coma cluster via NASA/ESA Hubble

    But most of the real work was done by Vera Rubin a Woman in STEM

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


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


    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    See the full article here .


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    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.

    LUX’s mission was to scour the universe for WIMPs, vetoing all other signatures. It would continue to do just that for another three years before it was decommissioned in 2016.

    In the midst of the excitement over first results, the LUX collaboration was already casting its gaze forward. Planning for a next-generation dark matter experiment at Sanford Lab was already under way. Named LUX-ZEPLIN (LZ), the next-generation experiment would increase the sensitivity of LUX 100 times.

    SLAC physicist Tom Shutt, a previous co-spokesperson for LUX, said one goal of the experiment was to figure out how to build an even larger detector.
    “LZ will be a thousand times more sensitive than the LUX detector,” Shutt said. “It will just begin to see an irreducible background of neutrinos that may ultimately set the limit to our ability to measure dark matter.”
    We celebrate five years of LUX, and look into the steps being taken toward the much larger and far more sensitive experiment.

    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

    U Washington Majorana Demonstrator Experiment at SURF

    The MAJORANA DEMONSTRATOR will contain 40 kg of germanium; up to 30 kg will be enriched to 86% in 76Ge. The DEMONSTRATOR will be deployed deep underground in an ultra-low-background shielded environment in the Sanford Underground Research Facility (SURF) in Lead, SD. The goal of the DEMONSTRATOR is to determine whether a future 1-tonne experiment can achieve a background goal of one count per tonne-year in a 4-keV region of interest around the 76Ge 0νββ Q-value at 2039 keV. MAJORANA plans to collaborate with GERDA for a future tonne-scale 76Ge 0νββ search.

    LBNL LZ project at SURF, Lead, SD, USA

     
  • richardmitnick 9:33 am on October 15, 2018 Permalink | Reply
    Tags: A Hefty WIMP Detector, , Large Underground Xenon (LUX) experiment, LZ experiment a $70 million upgrade and unification of the LUX and the UK-based ZEPLIN III teams, , , WIMPs-weakly interacting massive particles, Xenon1T project at Gran Sasso located in the Abruzzo region of central Italy   

    From UC Santa Barbara: “A Hefty WIMP Detector” 

    UC Santa Barbara Name bloc
    From UC Santa Barbara

    October 15, 2018
    Harrison Tasoff

    Installation of a detector designed by UC Santa Barbara physicists is underway at the LZ dark matter experiment.

    LBNL LZ project at SURF, Lead, SD, USA

    LZ Dark Matter Experiment at SURF lab

    UC Santa Barbara postdoctoral scientist Sally Shaw stands with one of the four large acrylic tanks fabricated for the LZ dark matter experiment’s outer detector.

    There’s a big hole in our current understanding of what makes up the universe. Normal matter — the stuff in people, planets and pulsars — can account for only 16 percent of the mass in the universe. Scientists know there’s more out there because they can see its effects: Its gravity bends light from distant sources and keeps galaxies from spinning themselves apart.

    Coma cluster via NASA/ESA Hubble

    Fritz Zwicky, Fritz Zwicky, the Father of Dark Matter research public domain

    Fritz Zwicky discovered Dark Matter by his study of the Coma Cluster. His work was aided by Vera Rubin

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

    Dark matter doesn’t appear to interact with normal matter via electromagnetism or through the strong nuclear force, which is known for binding particles together in the nuclei of atoms. Aside from gravity, that leaves one other force: the weak force, which is involved in radioactive decay. A leading hypothesis is that dark matter may be composed of exotic particles that have a high mass and interact with normal matter only through gravity and the weak force. Scientists call these weakly interacting massive particles, or WIMPs, and the search is on to find out if they exist.

    UC Santa Barbara physics professors Harry Nelson and Michael Witherell (now the director of Lawrence Berkeley Laboratory) have researched dark matter since the 1980s. About 10 years ago, some of their collaborators proved that liquid xenon was a superb medium for detecting WIMPs. Nelson and Witherell joined to help put together the Large Underground Xenon (LUX) experiment.

    The experiment was essentially a 32-gallon vat of liquid xenon that could detect when a single xenon atom was struck by a WIMP. It was located at the Sanford Underground Research Facility, roughly a mile under the Black Hills of South Dakota. This mile of rock shields the detector from the stream of particles that shower down on Earth’s surface every day. “We led the world in sensitivity in the hunt for WIMPs,” said Nelson.

    Since LUX came online in 2013, a number of similar, larger detectors in Italy and China joined the hunt. An international race was underway, and the LUX team proposed the LZ experiment, a $70 million upgrade and unification of the LUX and the UK-based ZEPLIN III teams. The LZ detector is designed to leapfrog the competition, and will contain 850 gallons of liquid xenon, about 27 times the volume of LUX.

    The new experiment will be so sensitive that it has to account for false positives from solar neutrinos, explained Nelson. Neutrinos are particles so ephemeral that co-discoverer and Nobel laureate Frederick Reines called them “the most tiny quantity of reality ever imagined by a human being.” Trillions of them pass straight through your body every second.

    Nelson, Witherell and a team of engineers and students designed the outer detector for the LZ experiment, starting in 2012. The outer detector consists primarily of four 12-foot-tall, clear acrylic tanks that will surround the core detector. The fabrication of these tanks proved a challenging, Nelson noted, giving credit to Reynolds Polymer Technology of Grand Junction, CO, who took on the task. The scientists will fill these tanks with a liquid that produces a small flash when hit by a particle, allowing them to distinguish a WIMP event from background radiation coming from radioactive impurities in the detector or the few conventional particles that manage to penetrate the rock above.

    Two of the four tanks, recently completed, will make the long journey underground later this month. “The logistics of building a large apparatus underground, accessible only by narrow tunnels, forces us to install the outer detector prior to the LZ liquid xenon detector,” Nelson said.

    The LZ experiment is scheduled to turn on in 2020 and should grab the lead in the hunt for WIMPs back from the Italians, whose current Xenon1T project contains about 271 gallons of liquid xenon. The Xenon1T team has plans for an upgrade to rival LZ, however, so the race is still on.

    XENON1T at Gran Sasso LABORATORI NAZIONALI del GRAN SASSO, located in the Abruzzo region of central Italy

    Gran Sasso LABORATORI NAZIONALI del GRAN SASSO, located in the Abruzzo region of central Italy

    “The incredible intellectual odyssey of the past 100,000 years, starting with modern humans questioning the nature of the element gold up to the very recent discovery of the Higgs particle, covers only one-sixth of the matter in the universe,” said Nelson. “Should LZ see a WIMP signal, it will mark the beginning of a new era of exploration and discovery.”

    Additional project collaborators at UC Santa Barbara include postdoctoral scientist Sally Shaw; engineers Susanne Kyre, Dano Pagenkopf and Dean White; and graduate students Scott Haselschwardt, Curt Nehrkorn and Melih Solmaz. The LZ group is supported by the U.S. Department of Energy’s Office of High Energy Physics.

    See the full article here .


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    Please help promote STEM in your local schools.

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    UC Santa Barbara Seal
    The University of California, Santa Barbara (commonly referred to as UC Santa Barbara or UCSB) is a public research university and one of the 10 general campuses of the University of California system. Founded in 1891 as an independent teachers’ college, UCSB joined the University of California system in 1944 and is the third-oldest general-education campus in the system. The university is a comprehensive doctoral university and is organized into five colleges offering 87 undergraduate degrees and 55 graduate degrees. In 2012, UCSB was ranked 41st among “National Universities” and 10th among public universities by U.S. News & World Report. UCSB houses twelve national research centers, including the renowned Kavli Institute for Theoretical Physics.

     
  • richardmitnick 2:39 pm on May 28, 2018 Permalink | Reply
    Tags: , , , , , The hunt for Dark Natter, WIMPs-weakly interacting massive particles, XENON1T at Gran Sasso   

    From Columbia University The XENON1T experiment via interactions.org: “XENON1T probes deeper into Dark Matter WIMPs, with 1300 kg of cold Xe atoms” 

    Columbia U bloc

    From Columbia University

    interactions.org

    XENON1T at Gran Sasso LABORATORI NAZIONALI del GRAN SASSO, located in the Abruzzo region of central Italy

    Results from XENON1T, the world’s largest and most sensitive detector dedicated to a direct search for Dark Matter in the form of Weakly Interacting Massive Particles (WIMPs), are reported today (Monday, 28th May) by the spokesperson, Prof. Elena Aprile of Columbia University, in a seminar at the hosting laboratory, the INFN Laboratori Nazionali del Gran Sasso (LNGS), in Italy.

    The international collaboration of more than 165 researchers from 27 institutions, has successfully operated XENON1T, collecting an unprecedentedly large exposure of about 1 tonne x year with a 3D imaging liquid xenon time projection chamber. The data are consistent with the expectation from background, and place the most stringent limit on spin-independent interactions of WIMPs with ordinary matter for a WIMP mass higher than 6 GeV/c². The sensitivity achieved with XENON1T is almost four orders of magnitude better than that of XENON10, the first detector of the XENON Dark Matter project, which has been hosted at LNGS since 2005. Steadily increasing the fiducial target mass from the initial 5 kg to the current 1300 kg, while simultaneously decreasing the background rate by a factor 5000, the XENON collaboration has continued to be at the forefront of Dark Matter direct detection, probing deeper into the WIMP parameter space.

    WIMPs are a class of Dark Matter candidates which are being frantically searched with experiments at the Large Hadron Collider, in space, and on Earth. Even though about a billion WIMPs are expected to cross a surface of one square meter per second on Earth, they are extremely difficult to detect. Results from XENON1T show that WIMPs, if they indeed comprise the Dark Matter in our galaxy, will result in a rare signal, so rare that even the largest detector built so far cannot see it directly. XENON1T is a cylindrical detector of approximately one meter height and diameter, filled with liquid xenon at -95 °C, with a density three times that of water. In XENON1T, the signature of a WIMP interaction with xenon atoms is a tiny flash of scintillation light and a handful of ionization electrons, which themselves are turned into flashes of light. Both light signals are simultaneously recorded with ultra-sensitive photodetectors, giving the energy and 3D spatial information on an event-by-event basis.

    2
    XENON1T installation in the underground hall of Laboratori Nazionali del Gran Sasso. The three story building houses various auxiliary systems. The cryostat containing the LXeTPC is located inside the large water tank next to the building. Photo by Roberto Corrieri and Patrick De Perio.

    In developing this unique type of detector to search for a rare WIMP signal, many challenges had to be overcome; first and foremost the reduction of the overwhelmingly large background from many sources, from radioactivity to cosmic rays. Today, XENON1T is the largest Dark Matter experiment with the lowest background ever measured, counting a mere 630 events in one year and one tonne of xenon in the energy region of interest for a WIMP search. The search results, submitted to Physical Review Letters, are based on 1300 kg out of the total 2000 kg active xenon target and 279 days of data, making it the first WIMP search with a noble liquid target exposure of 1.0 tonne x year. Only two background events were expected in the innermost, cleanest region of the detector, but none were detected, setting the most stringent limit on WIMPs with masses above 6 GeV/c² to date. XENON1T continues to acquire high-quality data and the search will continue until it will be upgraded with a larger mass detector, being developed by the collaboration. With another factor of four increase in fiducial target mass, and ten times less background rate, XENONnT will be ready in 2019 for a new exploration of particle Dark Matter at a level of sensitivity nobody imagined when the project started in 2002.

    The international collaboration of more than 165 researchers from 27 institutions, has successfully operated XENON1T, collecting an unprecedentedly large exposure of about 1 tonne x year with a 3D imaging liquid xenon time projection chamber.

    Columbia University, New York, USA
    PI and Spokesperson of XENON: Elena Aprile

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionale del Gran Sasso, l’Aquila, Italy
    PI: Walter Fulgione

    Istituto Nazionale di Fisica Nucleare, Torino, Italy
    PI: Giancarlo Trinchero

    Johannes Gutenberg University, Mainz, Germany
    PI: Uwe Oberlack

    Max-Planck-Institut für Kernphysik, Heidelberg, Germany
    PI: Manfred Lindner

    Nikhef & GRAPPA/University of Amsterdam, the Netherlands
    PI: Patrick Decowski

    Purdue University, West Lafayette, USA
    PI: Rafael Lang

    Rensselaer Polytechnic Institute, Troy, USA
    PI: Ethan Brown

    Rice University, Houston, USA
    PI: Petr Shagin

    Subatech, Nantes, France
    PI: Dominique Thers

    University of Bern, Switzerland
    PI: Marc Schumann

    Istituto Nazionale di Fisica Nucleare Bologna and University of Bologna, Italy
    PI: Gabriella Sartorelli

    University of California, Los Angeles, USA
    PI: Hanguo Wang

    University of California, San Diego, USA
    PI: Kaixuan Ni

    University of Chicago, USA
    PI: Luca Grandi

    University of Coimbra, Portugal
    PI: José Matias-Lopes

    University of Münster, Germany
    PI: Christian Weinheimer

    University of Zürich, Switzerland
    PI: Laura Baudis

    Weizmann Institute of Science, Rehovot, Israel
    PI: Ranny Budnik

    NYU Abu Dhabi, United Arab Emirates
    PI: Francesco Arneodo

    Stockholm University, Sweden
    PI: Jan Conrad

    The data are consistent with the expectation from background, and place the most stringent limit on spin-independent interactions of WIMPs with ordinary matter for a WIMP mass higher than 6 GeV/c². The sensitivity achieved with XENON1T is almost four orders of magnitude better than that of XENON10, the first detector of the XENON Dark Matter project, which has been hosted at LNGS since 2005. Steadily increasing the fiducial target mass from the initial 5 kg to the current 1300 kg, while simultaneously decreasing the background rate by a factor 5000, the XENON collaboration has continued to be at the forefront of Dark Matter direct detection, probing deeper into the WIMP parameter space.

    WIMPs are a class of Dark Matter candidates which are being frantically searched with experiments at the Large Hadron Collider, in space, and on Earth. Even though about a billion WIMPs are expected to cross a surface of one square meter per second on Earth, they are extremely difficult to detect. Results from XENON1T show that WIMPs, if they indeed comprise the Dark Matter in our galaxy, will result in a rare signal, so rare that even the largest detector built so far cannot see it directly. XENON1T is a cylindrical detector of approximately one meter height and diameter, filled with liquid xenon at -95 °C, with a density three times that of water. In XENON1T, the signature of a WIMP interaction with xenon atoms is a tiny flash of scintillation light and a handful of ionization electrons, which themselves are turned into flashes of light. Both light signals are simultaneously recorded with ultra-sensitive photodetectors, giving the energy and 3D spatial information on an event-by-event basis.

    See the full article here .


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    Columbia University was founded in 1754 as King’s College by royal charter of King George II of England. It is the oldest institution of higher learning in the state of New York and the fifth oldest in the United States.

     
  • richardmitnick 12:01 pm on May 15, 2018 Permalink | Reply
    Tags: Dark Matter experiments, , , SuperCDMS (Cryogenic Dark Matter Search), , WIMPs-weakly interacting massive particles   

    From Sanford Underground Research Facility: “SD Mines develops radon reduction system for LZ, SuperCDMS” 

    SURF logo
    Sanford Underground levels

    From Sanford Underground Research Facility

    May 14, 2018
    Constance Walter

    1
    Radon reduction researchers pictured with the machine they designed from left): SD Mines physics graduate student Joseph Street, Richard Schnee, Ph.D., along with lab technicians David Molash and Christine Hjelmfelt. Charles Michael Ray, SD Mines

    In the coming months, researchers will begin building the LUX-ZEPLIN dark matter experiment in a surface cleanroom at the Sanford Underground Research Facility (Sanford Lab).

    LBNL Lux Zeplin project at SURF

    Once the detector is assembled, a team will carefully move the highly sensitive physics equipment to its home on the 4850 Level of Sanford Lab.

    But before that can happen, there’s some work that needs to be done to ensure the experiment remains free of backgrounds that could interfere with the results. That’s where Dr. Richard Schnee and a team from the South Dakota School of Mines & Technology come in. Schnee, who is head of the physics department at SD Mines and a collaborator with LZ, heads up the SD Mines team that designed a radon reduction system for the experiment.

    “Our detectors need very low levels of radon,” Schnee said. While the radon levels at the 4850 Level are safe for humans, they are too high for sensitive experiments like LZ, which go deep underground to escape cosmic radiation, Schnee explained. “We will take regular air from the facility and the systems will reduce the levels by 1,000 times or more.”

    LZ, a second-generation dark matter experiment, will continue the search for WIMPs—weakly interacting massive particles—begun by its much smaller predecessor LUX (Large Underground Xenon), which was named the most sensitive of its kind in 2013 and again in 2016.

    U Washington Large Underground Xenon at SURF, Lead, SD, USA

    LZ will hold 10 tons of liquid xenon, making it approximately 30 times larger and 100 times more sensitive than LUX.

    LZ is designed so that if a dark matter particle collides with a xenon atom, it will produce a flash of light followed by a second flash of light when the electrons produced in the liquid xenon chamber drift to its top. The light pulses, picked up by a series of about 500 photo multiplier tubes lining the massive tank—over four times more than were installed in LUX—will carry the telltale fingerprint of the particles that created them.

    Additionally, LZ will include a component not present in LUX—nine acrylic tanks filled with a liquid scintillator will form a veto system around the experiment, allowing researchers to better recognize a WIMP if they see one.

    The system designed by the SD Mines team focuses specifically on filtering out radon particles to produce the ultra-pure air needed for the acrylic tanks and other components of LZ located in the same water tank that held LUX. The team is also helping ensure the parts used to build the experiments are relatively free of radon.

    “The real problem for these super sensitive dark mater detectors are the radon daughters that are radioactive,” Schnee said. Even miniscule amounts of radioactive particles could contaminate and throw off the experiments—so the work of Schnee and his team is critical.

    “We are very excited to have SD Mines as a partner in producing a major component for LZ, a world-leading dark matter experiment,” said Mike Headley, executive director the South Dakota Science and Technology Authority.

    LZ is in a global race to discover dark matter. One competitor, SuperCDMS (Cryogenic Dark Matter Search), which will be located at SNOLab in Canada, is using germanium to search for WIMPs. And SD Mines is designing a radon reduction system for that experiment as well, Schnee said.

    SNOLAB, a Canadian underground physics laboratory at a depth of 2 km in Vale’s Creighton nickel mine in Sudbury, Ontario


    SNOLAB, Sudbury, Ontario, Canada.

    LBNL SuperCDMS, at SNOLAB (Vale Inco Mine, Sudbury, Canada)


    LBNL SuperCDMS, at SNOLAB (Vale Inco Mine, Sudbury, Canada)


    LBNL Super CDMS, at SNOLAB (Vale Inco Mine, Sudbury, Canada)

    SNOLab is the deepest underground laboratory in North America at 6,800 feet deep. Although the experiments are competitors, Schnee said they actually complement each other as they are searching for dark matter in different areas. To use a metaphor, if dark matter were a lost child in a large cornfield, LZ would be looking in one part of the field, and SuperCDMS would be looking in another. Both projects will begin operations in the early 2020s. SD Mines is one of 26 institutions working on the SuperCDMS and one of 37 institutions working on LZ.

    Headley attributes the expanding role of SD Mines’ in research at Sanford Lab and other international experiments to the Ph.D. program in South Dakota. SD Mines and the University of South Dakota offer a joint program and each graduated Ph.D. students in 2017.

    “With the implementation of the Ph.D. program in 2012, South Dakota institutions are attracting high-quality professors and students,” Headley said. “It’s impressive to see them deliver such an important component for LZ, but also on other experiments around the world.”

    To learn more about the physics program at SD Mines, go to http://www.sdsmt.edu; to read the full press release about SD Mines work on LZ and SuperCDMS, go to https://www.sdsmt.edu/Research/.

    You can learn more about LZ at http://lz.lbl.gov/detector/and SCDMS at https://supercdms.slac.stanford.edu.

    See the full article here .

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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 9:01 am on May 7, 2018 Permalink | Reply
    Tags: , , Construction Begins on One of the World’s Most Sensitive Dark Matter Experiments, , , , , , SuperCDMS SNOLAB experiment, WIMPs-weakly interacting massive particles   

    From SLAC Lab: “Construction Begins on One of the World’s Most Sensitive Dark Matter Experiments” 


    From SLAC Lab

    May 7, 2018

    Press Office Contact: Andrew Gordon,
    agordon@slac.stanford.edu
    (650) 926-2282

    Written by Manuel Gnida

    1
    The future SuperCDMS SNOLAB experiment will hunt for weakly interacting massive particles (WIMPs), hypothetical components of dark matter. If a WIMP (white trace) strikes an atom inside the experiment’s detector crystals (gray), it will cause the crystal lattice to vibrate (blue). The collision will also send electrons (red) through the crystal that enhance the vibrations. (Greg Stewart/SLAC National Accelerator Laboratory)

    2
    The future SuperCDMS SNOLAB experiment will hunt for weakly interacting massive particles (WIMPs), hypothetical components of dark matter. This photo shows one of the experiment’s detector crystals within its protective copper housing. (Andy Freeberg/SLAC National Accelerator Laboratory)

    3
    SLAC’s Paul Brink handles the SuperCDMS SNOLAB engineering tower. (Chris Smith/SLAC National Accelerator Laboratory)

    4
    A SuperCDMS SNOLAB detector, fabricated at Texas A&M University. (Matt Cherry/SuperCDMS collaboration/SLAC National Accelerator Laboratory)

    5
    Dan Bauer (left) and Mark Ruschman in Fermilab’s Lab G , where the SuperCDMS SNOLAB project is preparing to test the cryogenics system for the new experiment. (Reidar Hahn/Fermi National Accelerator Laboratory)

    6
    Fermilab’s Mark Ruschman tests prototypes for the SuperCDMS SNOLAB cryogenics system. (Reidar Hahn/Fermi National Accelerator Laboratory)

    The SuperCDMS SNOLAB project, a multi-institutional effort led by SLAC, is expanding the hunt for dark matter to particles with properties not accessible to any other experiment.

    SNOLAB, Sudbury, Ontario, Canada.

    The U.S. Department of Energy has approved funding and start of construction for the SuperCDMS SNOLAB experiment, which will begin operations in the early 2020s to hunt for hypothetical dark matter particles called weakly interacting massive particles, or WIMPs. The experiment will be at least 50 times more sensitive than its predecessor, exploring WIMP properties that can’t be probed by other experiments and giving researchers a powerful new tool to understand one of the biggest mysteries of modern physics.

    The DOE’s SLAC National Accelerator Laboratory is managing the construction project for the international SuperCDMS collaboration of 111 members from 26 institutions, which is preparing to do research with the experiment.

    “Understanding dark matter is one of the hottest research topics – at SLAC and around the world,” said JoAnne Hewett, head of SLAC’s Fundamental Physics Directorate and the lab’s chief research officer. “We’re excited to lead the project and work with our partners to build this next-generation dark matter experiment.”

    With the DOE approvals, known as Critical Decisions 2 and 3, the researchers can now build the experiment. The DOE Office of Science will contribute $19 million to the effort, joining forces with the National Science Foundation ($12 million) and the Canada Foundation for Innovation ($3 million).

    “Our experiment will be the world’s most sensitive for relatively light WIMPs – in a mass range from a fraction of the proton mass to about 10 proton masses,” said Richard Partridge, head of the SuperCDMS group at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), a joint institute of SLAC and Stanford University. “This unparalleled sensitivity will create exciting opportunities to explore new territory in dark matter research.”

    An Ultracold Search 6,800 Feet Underground

    Scientists know that visible matter in the universe accounts for only 15 percent of all matter. The rest is a mysterious substance, called dark matter. Due to its gravitational pull on regular matter, dark matter is a key driver for the evolution of the universe, affecting the formation of galaxies like our Milky Way. It therefore is fundamental to our very own existence.

    But scientists have yet to find out what dark matter is made of. They believe it could be composed of dark matter particles, and WIMPs are top contenders. If these particles exist, they would barely interact with their environment and fly right through regular matter untouched. However, every so often, they could collide with an atom of our visible world, and dark matter researchers are looking for these rare interactions.

    7
    The centerpiece of the SuperCDMS SNOLAB experiment will be four detector towers (left), each containing six detector packs. The towers will be mounted inside the SNOBOX (right), a vessel in which the detector packs will be cooled to almost absolute zero temperature. (Greg Stewart/SLAC National Accelerator Laboratory)

    In the SuperCDMS SNOLAB experiment, the search will be done using silicon and germanium crystals, in which the collisions would trigger tiny vibrations. However, to measure the atomic jiggles, the crystals need to be cooled to less than minus 459.6 degrees Fahrenheit – a fraction of a degree above absolute zero temperature. These ultracold conditions give the experiment its name: Cryogenic Dark Matter Search, or CDMS. The prefix “Super” indicates an increased sensitivity compared to previous versions of the experiment.

    The collisions would also produce pairs of electrons and electron deficiencies that move through the crystals, triggering additional atomic vibrations that amplify the signal from the dark matter collision. The experiment will be able to measure these “fingerprints” left by dark matter with sophisticated superconducting electronics.

    The experiment will be assembled and operated at the Canadian laboratory SNOLAB – 6,800 feet underground inside a nickel mine near the city of Sudbury. It’s the deepest underground laboratory in North America. There it will be protected from high-energy particles, called cosmic radiation, which can create unwanted background signals.

    8
    The SuperCDMS dark matter experiment will be located at the Canadian laboratory SNOLAB, 2 kilometers (6,800 feet) underground inside a nickel mine near the city of Sudbury. It’s the deepest underground laboratory in North America. There it will be protected from high-energy particles, called cosmic radiation, which can create unwanted background signals. (Greg Stewart/SLAC National Accelerator Laboratory; inset: SNOLAB)

    “SNOLAB is excited to welcome the SuperCDMS SNOLAB collaboration to the underground lab,” said Kerry Loken, SNOLAB project manager. “We look forward to a great partnership and to supporting this world-leading science.”

    Over the past months, a detector prototype has been successfully tested at SLAC. “These tests were an important demonstration that we’re able to build the actual detector with high enough energy resolution, as well as detector electronics with low enough noise to accomplish our research goals,” said KIPAC’s Paul Brink, who oversees the detector fabrication at Stanford.

    Together with seven other collaborating institutions, SLAC will provide the experiment’s centerpiece of four detector towers, each containing six crystals in the shape of oversized hockey pucks. The first tower could be sent to SNOLAB by the end of 2018.

    “The detector towers are the most technologically challenging part of the experiment, pushing the frontiers of our understanding of low-temperature devices and superconducting readout,” said Bernard Sadoulet, a collaborator from the University of California, Berkeley.

    A Strong Collaboration for Extraordinary Science

    In addition to SLAC, two other national labs are involved in the project. Fermi National Accelerator Laboratory is working on the experiment’s intricate shielding and cryogenics infrastructure, and Pacific Northwest National Laboratory is helping understand background signals in the experiment, a major challenge for the detection of faint WIMP signals.

    9
    Slideshow of SuperCDMS SNOLAB photos. For more images, visit the SuperCDMS SNOLAB photostream on Flickr.

    A number of U.S. and Canadian universities also play key roles in the experiment, working on tasks ranging from detector fabrication and testing to data analysis and simulation. The largest international contribution comes from Canada and includes the research infrastructure at SNOLAB.

    “We’re fortunate to have a close-knit network of strong collaboration partners, which is crucial for our success,” said KIPAC’s Blas Cabrera, who directed the project through the CD-2/3 approval milestone. “The same is true for the outstanding support we’re receiving from the funding agencies in the U.S. and Canada.”

    Fermilab’s Dan Bauer, spokesperson of the SuperCDMS collaboration said, “Together we’re now ready to build an experiment that will search for dark matter particles that interact with normal matter in an entirely new region.”

    SuperCDMS SNOLAB will be the latest in a series of increasingly sensitive dark matter experiments. The most recent version, located at the Soudan Mine in Minnesota, completed operations in 2015.

    “The project has incorporated lessons learned from previous CDMS experiments to significantly improve the experimental infrastructure and detector designs for the experiment,” said SLAC’s Ken Fouts, project manager for SuperCDMS SNOLAB. “The combination of design improvements, the deep location and the infrastructure support provided by SNOLAB will allow the experiment to reach its full potential in the search for low-mass dark matter.”

    For more information on the SuperCDMS SNOLAB project and the SuperCDMS collaboration, check out this website:

    SuperCDMS SNOLAB Website

    See the full article here .

    Please help promote STEM in your local schools.

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    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.

     
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