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  • richardmitnick 11:07 am on January 3, 2018 Permalink | Reply
    Tags: Compact Accelerator System for Performing Astrophysical Research (CASPAR) collaboration, Facebook visit - watch the included video, , Lab Director looks back at 2017, , LBNL’s Enhanced Geothermal Systems Collaboration (EGS Collab), , LUX-ZEPLIN (LZ) dark matter-hunting experiment, , Ross Shaft rehabilitation project,   

    From SURF: “Lab Director looks back at 2017” A Gigantic and Important Laboratory in The U.S. 

    SURF logo
    Sanford Underground levels

    Sanford Underground Research facility

    Executive Director Mike Headley


    2017 has been an exciting year at Sanford Lab. We’ve seen tremendous progress on current and future experiments, including dark matter and neutrino research; the ongoing efforts of the Black Hills Underground Campus; Education and Outreach; and the Ross Shaft rehabilitation project, which reached the 4850 Level in October. Underpinning the success of our projects is our continued commitment to safety at Sanford Lab. I am so proud of our staff, researchers and contractors for their focus on safety every day.

    The success of 2017 is directly related to our strong partnerships with many organizations, including the various science collaborations at Sanford Lab; Fermilab, which has oversight responsibilities for our operations activities for the Department of Energy and is the lead DOE laboratory for the Long-Baseline Neutrino Facility and Deep Underground Neutrino Experiment (LBNF/DUNE) project; and Lawrence Berkeley National Laboratory. I also want to thank the State of South Dakota and the SDSTA Board of Directors for their strong support of the world-leading underground science at Sanford Lab.

    LBNF/DUNE Groundbreaking

    On July 21, we celebrated the groundbreaking of the Long-Baseline Neutrino Facility, which officially kicked off a new era in particle physics. We’re proud to be one of the sites hosting this international mega-science project, which will be the largest in the United States, and to be working alongside Fermilab and the DUNE collaboration. LBNF/DUNE has the potential to unlock the mysteries of neutrinos, which could explain more about how the universe works and why matter exists at all. At its peak, construction of LBNF is expected to create almost 2,000 jobs throughout South Dakota and a similar number of jobs in Illinois. The experiment will take approximately 10 years to build and will operate for about 20 years.

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    International support

    The LBNF/DUNE project garnered support from CERN in 2016, marking the first time the European-based science facility supported a major project outside of Europe. In another first, the United Kingdom signed an umbrella agreement with the United States on September 20 that commits $88 million toward the LBNF/DUNE project along with accelerator advancements at Fermilab. The $88 million in funding makes the UK the largest country investor in the project outside of the United States.

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    CM/GC selected: On Aug. 9, a new team officially signed on to help prepare for the excavation and construction of LBNF. Fermi Research Alliance LLC, which operates Fermilab, awarded Kiewit/Alberici Joint Venture (KAJV) a contract to begin laying the groundwork for the excavation for LBNF, the facility that will support DUNE. KAJV will help finalize design and excavation plans for LBNF and oversee the excavation and removal of more than 800,000 tons of rock, as well as the outfitting of the DUNE caverns.

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    Dark Matter

    For several years, we hosted LUX, one of the world’s most sensitive dark matter experiments. Now, we’re gearing up for the next-generation experiment, LUX-ZEPLIN (LZ). The collaboration had a positive directors’ progress review in November and will begin surface assembly activities in early 2018. We are proud to have made major contributions to LZ, including investing in 80 percent of the xenon, which is being purified at SLAC National Accelerator Laboratory. We’ve also updated the Surface Lab cleanroom (pictured above) and built a radon reduction facility. The experiment is expected to begin operations in 2020 and run for five years.

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    LUX on display

    Visitors to the Sanford Lab Homestake Visitor Center can now view the decommissioned Large Underground Xenon (LUX) experiment on display as an interactive exhibit. On July 18, researchers unveiled the new exhibit, which features a window that allows visitors to view the inside of the detector: copper grids, white Teflon plates and a depiction of the wire grids that were vital to the success of the experiment. Additionally, an interactive kiosk explains the history of the LUX detector and all of the associated parts that are shown in the exhibit, and an actual PMT, one of 120 used in the experiment.

    Read more


    CASPAR Ribbon Cutting

    In a major step forward, the Compact Accelerator System for Performing Astrophysical Research (CASPAR) collaboration achieved first beam and celebrated with a ribbon-cutting ceremony on July 12. CASPAR’s 50-foot long accelerator uses radio-frequency energy to produce a beam of protons or alpha particles from hydrogen or helium gas. The ions enter the accelerating tube, which is kept at high vacuum, then are directed down the beamline using magnets. The particles crash into a target, releasing the same neutrons that fuel the nuclear reactions in stars and produce a large amount of the heavy elements. The collaboration will begin full operations this year.

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    Majorana reports results

    After years of planning and building its experiment, the Majorana Demonstrator collaboration announced its initial physics results. The team is looking for a rare type of radioactive decay called neutrinoless double-beta decay, which could answer fundamental questions about the universe, including why there is an imbalance of matter and antimatter in the universe and why we even exist. The Majorana Demonstrator collaboration needed to show it could achieve the low backgrounds required to see this rare physics event. And the team surpassed its goals, reducing backgrounds to a level that shows promise for a next-generation experiment that will be much larger.

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    We’re excited to have a new geology collaboration at Sanford Lab: LBNL’s Enhanced Geothermal Systems Collaboration (EGS Collab), which is studying geothermal systems, a clean-energy technology that could power up to 100 million American homes. The SIGMA-V (Stimulation Investigations for Geothermal Modeling and Analysis) team has been collecting data that will inform better predictive and geomechanic models of the subsurface of the earth by drilling several 60-meter long boreholes on the 4850 Level. The data will be applied toward the Frontier Observatory for Research in Geothermal Energy (FORGE), a flagship DOE geothermal project.

    Read more

    Community outreach

    Interest in what’s happening at Sanford Lab continues to grow. This year more than 2,000 people attended events hosted by Sanford Lab. During Neutrino Day 2017: Discovery, visitors to Lead participated in a practice eclipse balloon launch, hands-on education activities, video conferences from a mile underground and Fermilab, hoistroom tours and “wild science” and geology demonstrations, and learned all about 2017’s Nobel-winning physics experiment, LIGO, which discovered gravitational waves. We also hosted an Eclipse party and several Deep Talks presentations.

    Facebook visit

    Everywhere we go lately, we get asked about Mark Zuckerberg’s July 12 visit to Sanford Lab. The Facebook founder visited South Dakota, where he had lunch with ranchers in Piedmont, discussed net neutrality in Sturgis and stopped by the Sanford Underground Research Facility—all in a single day. In a live-stream video from the 4850 Level, Mr. Zuckerberg talked with Sanford Lab’s Dan Regan and Jaret Heise, and Cabot-Ann Christofferson, a member of the Majorana Collabortion to learn more about the community of Lead and the world-leading science taking place nearly a mile below the earth’s surface. So far, more than 4 million people have viewed the video. We were honored to host him and his team and appreciate his efforts to help Facebook users better understand who we are.

    Watch the live post

    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

  • richardmitnick 10:02 pm on February 13, 2017 Permalink | Reply
    Tags: , , , LUX-ZEPLIN (LZ) dark matter-hunting experiment, ,   

    From LBNL: “Next-Gen Dark Matter Detector in a Race to Finish Line” 

    Berkeley Logo

    Berkeley Lab

    February 13, 2017
    Glenn Roberts Jr.

    Light-amplifying devices known as photomultiplier tubes (PMTs), developed for use in the LUX-ZEPLIN (LZ) dark matter-hunting experiment, are prepared for a test at Brown University. This test bed, dubbed PATRIC, will be used to test over 600 PMTs in conditions simulating the temperature and pressure of the liquid xenon that will be used for LZ. (Credit: Brown University)

    The race is on to build the most sensitive U.S.-based experiment designed to directly detect dark matter particles. Department of Energy officials have formally approved a key construction milestone that will propel the project toward its April 2020 goal for completion.

    The LUX-ZEPLIN (LZ) experiment, which will be built nearly a mile underground at the Sanford Underground Research Facility (SURF) in Lead, S.D., is considered one of the best bets yet to determine whether theorized dark matter particles known as WIMPs (weakly interacting massive particles) actually exist. There are other dark matter candidates, too, such as “axions” or “sterile neutrinos,” which other experiments are better suited to root out or rule out.

    SURF logo
    SURF – Sanford Underground Research Facility at Lead, SD, USA

    The fast-moving schedule for LZ will help the U.S. stay competitive with similar next-gen dark matter direct-detection experiments planned in Italy and China.

    This image shows a cutaway rendering of the LUX-ZEPLIN (LZ) detector that will search for dark matter nearly a mile below ground. An array of detectors, known as photomultiplier tubes, at the top and bottom of the liquid xenon tank are designed to pick up particle signals. (Credit: Matt Hoff/Berkeley Lab)

    On Feb. 9, the project passed a DOE review and approval stage known as Critical Decision 3 (CD-3), which accepts the final design and formally launches construction.

    “We will try to go as fast as we can to have everything completed by April 2020,” said Murdock “Gil” Gilchriese, LZ project director and a physicist at the DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab), the lead lab for the project. “We got a very strong endorsement to go fast and to be first.” The LZ collaboration now has about 220 participating scientists and engineers who represent 38 institutions around the globe.

    The nature of dark matter—which physicists describe as the invisible component or so-called “missing mass” in the universe that would explain the faster-than-expected spins of galaxies, and their motion in clusters observed across the universe—has eluded scientists since its existence was deduced through calculations by Swiss astronomer Fritz Zwicky in 1933.

    The quest to find out what dark matter is made of, or to learn whether it can be explained by tweaking the known laws of physics in new ways, is considered one of the most pressing questions in particle physics.

    Successive generations of experiments have evolved to provide extreme sensitivity in the search that will at least rule out some of the likely candidates and hiding spots for dark matter, or may lead to a discovery.

    The underground home of LZ and its supporting systems are shown in this computerized rendering. (Credit: Matt Hoff/Berkeley Lab)

    LZ will be at least 50 times more sensitive to finding signals from dark matter particles than its predecessor, the Large Underground Xenon experiment (LUX), which was removed from SURF last year to make way for LZ. The new experiment will use 10 metric tons of ultra-purified liquid xenon, to tease out possible dark matter signals. Xenon, in its gas form, is one of the rarest elements in Earth’s atmosphere.

    “The science is highly compelling, so it’s being pursued by physicists all over the world,” said Carter Hall, the spokesperson for the LZ collaboration and an associate professor of physics at the University of Maryland. “It’s a friendly and healthy competition, with a major discovery possibly at stake.”

    This chart shows the sensitivity limits (solid-line curves) of various experiments searching for signs of theoretical dark matter particles known as WIMPs, with LZ (green dashed line) set to expand the search range. (Credit: Snowmass report, 2013)

    A planned upgrade to the current XENON1T experiment at National Institute for Nuclear Physics’ Gran Sasso Laboratory (the XENONnT experiment) in Italy, and China’s plans to advance the work on PandaX-II, are also slated to be leading-edge underground experiments that will use liquid xenon as the medium to seek out a dark matter signal.

    Assembly of the XENON1T TPC in the cleanroom. (Image: INFN)

    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


    Both of these projects are expected to have a similar schedule and scale to LZ, though LZ participants are aiming to achieve a higher sensitivity to dark matter than these other contenders.

    Hall noted that while WIMPs are a primary target for LZ and its competitors, LZ’s explorations into uncharted territory could lead to a variety of surprising discoveries. “People are developing all sorts of models to explain dark matter,” he said. “LZ is optimized to observe a heavy WIMP, but it’s sensitive to some less-conventional scenarios as well. It can also search for other exotic particles and rare processes.”

    LZ is designed so that if a dark matter particle collides with a xenon atom, it will produce a prompt 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 light-amplifying 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.

    Inside LZ: When a theorized dark matter particle known as a WIMP collides with a xenon atom, the xenon atom emits a flash of light (gold) and electrons. The flash of light is detected at the top and bottom of the liquid xenon chamber. An electric field pushes the electrons to the top of the chamber, where they generate a second flash of light (red). (Credit: SLAC National Accelerator Laboratory)

    Daniel Akerib, Thomas Shutt, and Maria Elena Monzani are leading the LZ team at SLAC National Accelerator Laboratory. The SLAC effort includes a program to purify xenon for LZ by removing krypton, an element that is typically found in trace amounts with xenon after standard refinement processes. “We have already demonstrated the purification required for LZ and are now working on ways to further purify the xenon to extend the science reach of LZ,” Akerib said.

    SLAC and Berkeley Lab collaborators are also developing and testing hand-woven wire grids that draw out electrical signals produced by particle interactions in the liquid xenon tank. Full-size prototypes will be operated later this year at a SLAC test platform. “These tests are important to ensure that the grids don’t produce low-level electrical discharge when operated at high voltage, since the discharge could swamp a faint signal from dark matter,” said Shutt.

    Assembly of the prototype for the LZ detector’s core, known as a time projection chamber (TPC). From left: Jeremy Mock (State University of New York/Berkeley Lab), Knut Skarpaas, and Robert Conley. (Credit: SLAC National Accelerator Laboratory)

    Hugh Lippincott, a Wilson Fellow at Fermi National Accelerator Laboratory (Fermilab) and the physics coordinator for the LZ collaboration, said, “Alongside the effort to get the detector built and taking data as fast as we can, we’re also building up our simulation and data analysis tools so that we can understand what we’ll see when the detector turns on. We want to be ready for physics as soon as the first flash of light appears in the xenon.” Fermilab is responsible for implementing key parts of the critical system that handles, purifies, and cools the xenon.

    All of the components for LZ are painstakingly measured for naturally occurring radiation levels to account for possible false signals coming from the components themselves. A dust-filtering cleanroom is being prepared for LZ’s assembly and a radon-reduction building is under construction at the South Dakota site—radon is a naturally occurring radioactive gas that could interfere with dark matter detection. These steps are necessary to remove background signals as much as possible.

    A rendering of the Surface Assembly Laboratory in [at SURF] South Dakota where LZ components will be assembled before they are relocated underground. (Credit: LZ collaboration)

    The vessels that will surround the liquid xenon, which are the responsibility of the U.K. participants of the collaboration, are now being assembled in Italy. They will be built with the world’s most ultra-pure titanium to further reduce background noise.

    To ensure unwanted particles are not misread as dark matter signals, LZ’s liquid xenon chamber will be surrounded by another liquid-filled tank and a separate array of photomultiplier tubes that can measure other particles and largely veto false signals. Brookhaven National Laboratory is handling the production of another very pure liquid, known as a scintillator fluid, that will go into this tank.

    A production prototype of highly purified, gadolinium-doped scintillator fluid, viewed under ultraviolet light. Scintillator fluid will surround LZ’s xenon tank and will help scientists veto the background “noise” of unwanted particle signals. (Credit: Brookhaven National Laboratory)

    The cleanrooms will be in place by June, Gilchriese said, and preparation of the cavern where LZ will be housed is underway at SURF. Onsite assembly and installation will begin in 2018, he added, and all of the xenon needed for the project has either already been delivered or is under contract. Xenon gas, which is costly to produce, is used in lighting, medical imaging and anesthesia, space-vehicle propulsion systems, and the electronics industry.

    “South Dakota is proud to host the LZ experiment at SURF and to contribute 80 percent of the xenon for LZ,” said Mike Headley, executive director of the South Dakota Science and Technology Authority (SDSTA) that oversees SURF. “Our facility work is underway and we’re on track to support LZ’s timeline.”

    UK scientists, who make up about one-quarter of the LZ collaboration, are contributing hardware for most subsystems. Henrique Araújo, from Imperial College London, said, “We are looking forward to seeing everything come together after a long period of design and planning.”

    LZ participants conduct a quality-control inspection of photomultiplier tube bases that are being manufactured at Imperial College London. (Credit: Henrique Araújo /Imperial College London)

    Kelly Hanzel, LZ project manager and a Berkeley Lab mechanical engineer, added, “We have an excellent collaboration and team of engineers who are dedicated to the science and success of the project.” The latest approval milestone, she said, “is probably the most significant step so far,” as it provides for the purchase of most of the major components in LZ’s supporting systems.

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

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

    Both of these projects are expected to have a similar schedule and scale to LZ, though LZ participants are aiming to achieve a higher sensitivity to dark matter than these other contenders.

    See the full article here .

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