Tagged: Neutrinos Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 2:26 pm on August 24, 2016 Permalink | Reply
    Tags: Neutrinos, , , The $100 muon detector   

    From Symmetry: “The $100 muon detector” 

    Symmetry Mag

    Symmetry

    08/19/16
    By Laura Dattaro

    1
    Spencer Axani

    A doctoral student and his adviser designed a tabletop particle detector they hope to make accessible to budding young engineering physicists.

    When Spencer Axani was an undergraduate physics student, his background in engineering led him to a creative pipe dream: a pocket-sized device that could count short-lived particles called muons all day.

    Muons, heavier versions of electrons, are around us all the time, a byproduct of the cosmic rays that shoot out from supernovae and other high-energy events in space. When particles from those rays hit Earth’s atmosphere, they often decay into muons.

    Muons are abundant on the surface of the Earth, but in Axani’s University of Alberta underground office, shielded by the floors above, they might be few and far between. A pocket detector would be the perfect gadget for measuring the difference.

    Now a doctoral student at Massachusetts Institute of Technology, Axani has nearly made this device a reality. Along with an undergraduate student and Axani’s adviser, Janet Conrad, he’s developed a detector that sits on a desk and tallies the muons that pass by. The best part? The whole system can be built by students for under $100.

    “Compared to most detectors, it’s by far the cheapest and smallest I’ve found,” Axani says. “If you make 100,000 of these, it starts becoming a very large detector. Instrumenting airplanes and ships would let you start measuring cosmic ray rates around the world.”

    Particle physicists deal with cosmic rays all of the time, says Conrad, a physics professor at MIT. “Sometimes we love them, and sometimes we hate them. We love them if we can use them for calibration of our detectors, and we hate them if they provide a background for what it is that we are trying to do.”

    Conrad used small muon detectors similar to the one Axani dreamed about when leading a neutrino experiment at Fermi National Accelerator Laboratory called MiniBooNE. When a professor at the University of Alberta proposed adding mini-muon detectors to another neutrino experiment, Axani was ready to pitch in.

    FNAL/MiniBooNE
    FNAL/MiniBooNE

    The idea was to create muon detectors to add to IceCube, a neutrino detector built into the ice in Antarctica. They would be inserted into IceCube’s proposed low-energy upgrade, known as PINGU (Precision IceCube Next Generation Upgrade).

    U Wisconsin ICECUBE neutrino detector at the South Pole
    IceCube neutrino detector interior
    U Wisconsin ICECUBE neutrino detector at the South Pole

    IceCube PINGU
    IceCube PINGU

    First, they needed a prototype. Axani got to work and quickly devised a rough detector housed in PVC pipe. “It looked pretty lab,” Axani said. It also gave off a terrible smell, the result of using a liquid called toluene as a scintillator, a material that gives off light when hit by a charged particle.

    Over the next few months, Axani refined the device, switching to an odorless plastic scintillator and employing silicon photomultipliers (SiPM), which amplify the light from the scintillator into a signal that can be read. Adding some electronics allowed him to build a readout screen that ticks off the amount of energy from muon interactions and registers the time of the event.

    Sitting in Axani’s office, the counter shows a rate of one muon every few seconds, which is what they expected from the size of the detector. Though it’s fairly constant, even minor changes like increased humidity or heavy rain can alter it.

    Conrad and Axani have taken the detector down into the Boston subway, using the changes in the muon count to calculate the depth of the train tunnels. They’ve also brought it into the caverns of Fermilab’s neutrino experiments to measure the muon flux more than 300 feet underground.

    Axani wants to take it to higher elevations—say, in an airplane at 30,000 feet above sea level—where muon counts should be higher, since the particles have had less time to decay after their creation in the atmosphere.

    Fermilab physicist Herman White suggested taking one of the the tiny detectors on a ship to study muon counts at sea. Mapping out the muon rate around the globe at sea has never been achieved. Liquid scintillator can be harmful to marine life, and the high voltage and power consumption of the large devices present a safety hazard.

    While awaiting review of the PINGU upgrade, both Conrad and Axani see value in their project as an educational tool. With a low cost and simple instructions, the muon counter they created can be assembled by undergraduates and high school students, who would learn about machining, circuits, and particle physics along the way—no previous experience required.

    “The idea was, students building the detectors would develop skills typically taught in undergraduate lab classes,” Spencer says. “In return, they would end up with a device useful for all sorts of physics measurements.”

    Conrad has first-hand knowledge of how hands-on experience like this can teach students new skills. As an undergraduate at Swarthmore College, she took a course that taught all the basic abilities needed for a career in experimental physics: using a machine shop, soldering, building circuits. As a final project, she constructed a statue that she’s held on to ever since.

    Creating the statue helped Conrad cement the lessons she learned in the class, but the product was abstract, not a functioning tool that could be used to do real science.

    “We built a bunch of things that were fun, but they weren’t actually useful in any way,” Conrad says. “This [muon detector] takes you through all of the exercises that we did and more, and then produces something at the end that you would then do physics with.”

    Axani and Conrad published instructions for building the detector on the open-source physics publishing site arXiv, and have been reworking the project with the aim of making it accessible to high-school students. No math more advanced than division and multiplication is needed, Axani says. And the parts don’t need to be new, meaning students could potentially take advantage of leftovers from experiments at places like Fermilab.

    “This should be for students to build,” Axani says. “It’s a good project for creative people who want to make their own measurements.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 5:13 pm on August 23, 2016 Permalink | Reply
    Tags: , , , Hyper-Kamiokande, Neutrinos, , ,   

    From Physics Today: “Six reasons to get excited about neutrinos” 

    Physics Today bloc

    Physics Today

    23 August 2016
    Andrew Grant

    Extra Dimensions: New results and upcoming experiments offer hope that neutrinos hold the key to expanding the standard model.

    The headlines from the recent International Conference on High Energy Physics (ICHEP) in Chicago trended sad, focused on the dearth of discoveries from the Large Hadron Collider. (See, for example, “Prospective particle disappears in new LHC data.”) Yet there was some optimism to be found in the Windy City, particularly among neutrino physicists. Here are six reasons to believe that neutrinos might provide the window into new physics that the LHC has not:

    Neutrinos are proof that the standard model is wrong. Sure, we know that dark matter and dark energy are missing from the standard model. But neutrinos are standard-model members, and the theoretical predictions are wrong. Prevailing theory says that neutrinos are massless; the Nobel-winning experiments at the Sudbury Neutrino Observatory and Super-Kamiokande demonstrated definitively that neutrinos oscillate between three flavors (electron, muon, and tau) and thus have mass. André de Gouvêa, a theoretical physicist at Northwestern University, deems neutrinos the “only palpable evidence of physics beyond the standard model.” Everything we learn about neutrinos in the coming years is new physics.

    1
    This signal from May 2014 denotes the detection of an electron neutrino by Fermilab’s NOvA experiment. Credit: NOvA Neutrino Experiment.

    FNAL/NOvA experiment
    FNAL/NOvA experiment map

    Neutrinos’ ability to morph from one flavor to another is only now starting to be understood. Each of neutrinos’ three flavors is actually a quantum superposition of three different mass states. By understanding the interplay of the three mass states, characterized by parameters called mixing angles, physicists can pin down how neutrinos transform between flavors. Fresh data from the NOvA experiment at Fermilab near Chicago suggest that neutrino mixing may not be as simple as most theories predict.

    Neutrinos may exhibit charge conjugation–parity (CP) violation. All known examples of CP violation, in which particle decays proceed differently with matter than with antimatter, take place in processes involving quark-containing particles like kaons and B mesons. But at the Neutrino 2016 meeting in London and at ICHEP, the T2K experiment offered fresh data hinting at matter–antimatter asymmetry for neutrinos.

    T2K Experiment
    Super-Kamiokande
    T2K map
    T2K Experiment

    After firing beams of muon neutrinos and antineutrinos at the Super-Kamiokande detector in Japan, scientists expected to detect 23 electron neutrinos and 7 electron antineutrinos; instead they have spotted 32 and 4, respectively. T2K isn’t anywhere close to achieving a 5 σ result, but the evidence for CP violation seems to be growing as the experiment acquires more data.

    Neutrinos may be the first fundamental particles that are Majorana fermions. Because the neutrino is the only fermion that is electrically neutral, it is also the only one that could be a Majorana fermion, a particle that is identical to its antiparticle. Learning whether neutrinos are Majorana particles or typical Dirac fermions would provide invaluable insight as to how neutrinos acquired mass at the dawn of the universe, de Gouvêa says. To determine the nature of neutrinos, physicists are hunting for a process called neutrinoless double beta decay. In typical double beta decay, two neutrons transform into protons and emit a pair of antineutrinos. If those antineutrinos are Majorana particles, they could annihilate each other. A 16 August paper from the KamLAND-Zen experiment in Japan reports the most stringent limits for the rate of neutrinoless double beta decay, further constraining the possibility that neutrinos are Majorana particles.

    Another neutrino flavor may be waiting to be discovered. The discovery of a fourth neutrino flavor, the sterile neutrino, would make every particle physicist forget about the LHC’s particle drought. Such a neutrino could enable physicists to explain dark matter or the absence of antimatter in the universe. The Antarctic detector IceCube just reported a negative result in the hunt for a sterile neutrino, but results from prior experiments still leave some wiggle room for the particle’s existence.

    Multiple powerful neutrino experiments are on the horizon. The NOvA experiment is up and running and delivering data that, at least so far, seem to complement T2K’s hints of CP violation. Fermilab scientists are already excited about the Deep Underground Neutrino Experiment, which should come on line around 2025.

    FNAL LBNF/DUNE from FNAL to SURF
    FNAL LBNF/DUNE from FNAL to SURF

    Hyper-Kamiokande, a megadetector in Japan with a million-ton tank of water for neutrino detection, should start operations around the same time.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    “Our mission

    The mission of Physics Today is to be a unifying influence for the diverse areas of physics and the physics-related sciences.

    It does that in three ways:

    • by providing authoritative, engaging coverage of physical science research and its applications without regard to disciplinary boundaries;
    • by providing authoritative, engaging coverage of the often complex interactions of the physical sciences with each other and with other spheres of human endeavor; and
    • by providing a forum for the exchange of ideas within the scientific community.”

     
  • richardmitnick 9:55 am on August 23, 2016 Permalink | Reply
    Tags: , , Neutrinos, NuMI horn, ,   

    From FNAL: “Funneling fundamental particles” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

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

    August 22, 2016
    Molly Olmstead

    1
    The NuMI horn in the Main Injector brings particles into focus. Photo: Reidar Hahn

    Neutrinos are tricky. Although trillions of these harmless, neutral particles pass through us every second, they interact so rarely with matter that, to study them, scientists send a beam of neutrinos to giant detectors. And to be sure they have enough of them, scientists have to start with a very concentrated beam of neutrinos.

    To concentrate the beam, an experiment needs a special device called a neutrino horn.

    An experiment’s neutrino beam is born from a shower of short-lived particles, created when protons traveling close to the speed of light slam into a target. But that shower doesn’t form a tidy beam itself: That’s where the neutrino horn comes in.

    Once the accelerated protons smash into the target to create pions and kaons — the short-lived charged particles that decay into neutrinos — the horn has to catch and focus them by using a magnetic field. The pions and kaons have to be focused immediately, before they decay into neutrinos: Unlike the pions and kaons, neutrinos don’t interact with magnetic fields, which means we can’t focus them directly.

    Without the horn, an experiment would lose 95 percent of the neutrinos in its beam. Scientists need to maximize the number of neutrinos in the beam because neutrinos interact so rarely with matter. The more you have, the more opportunities you have to study them.

    “You have to have tremendous numbers of neutrinos,” said Jim Hylen, a beam physicist at Fermilab. “You’re always fighting for more and more.”

    Also known as magnetic horns, neutrino horns were invented at CERN by the Nobel Prize-winning physicist Simon van der Meer in 1961. A few different labs used neutrino horns over the following years, and Fermilab and J-PARC in Japan are the only major laboratories now hosting experiments with neutrino horns. Fermilab is one of the few places in the world that makes neutrino horns.

    “Of the major labs, we currently have the most expertise in horn construction here at Fermilab,” Hylen said.

    How they work

    The proton beam first strikes the target that sits inside or just upstream of the horn. The powerful proton beam would punch through the aluminum horn if it hit it, but the target, which is made of graphite or beryllium segments, is built to withstand the beam’s full power. When the target is struck by the beam, its temperature jumps by more than 700 degrees Fahrenheit, making the process of keeping the target-horn system cool a challenge involving a water-cooling system and a wind stream.

    Once the beam hits the target, the neutrino horn directs resulting particles that come out at wide angles back toward the detector. To do this, it uses magnetic fields, which are created by pulsing a powerful electrical current — about 200,000 amps — along the horn’s surfaces.

    “It’s essentially a big magnet that acts as a lens for the particles,” said physicist Bob Zwaska.

    The horns come in slightly different shapes, but they generally look on the outside like a metal cylinder sprouting a complicated network of pipes and other supporting equipment. On the inside, an inner conductor leaves a hollow tunnel for the beam to travel through.

    Because the current flows in one direction on the inner conductor and the opposite direction on the outer conductor, a magnetic field forms between them. A particle traveling along the center of the beamline will zip through that tunnel, escaping the magnetic field between the conductors and staying true to its course. Any errant particles that angle off into the field between the conductors are kicked back in toward the center.

    The horn’s current flows in a way that funnels positively charged particles that decay into neutrinos toward the beam and deflects negatively charged particles that decay into antineutrinos outward. Reversing the current can swap the selection, creating an antimatter beam. Experiments can run either beam and compare the data from the two runs. By studying neutrinos and antineutrinos, scientists try to determine whether neutrinos are responsible for the matter-antimatter asymmetry in the universe. Similarly, experiments can control what range of neutrino energies they target most by tuning the strength of the field or the shape or location of the horn.

    Making and running a neutrino horn can be tricky. A horn has to be engineered carefully to keep the current flowing evenly. And the inner conductor has to be as slim as possible to avoid blocking particles. But despite its delicacy, a horn has to handle extreme heat and pressure from the current that threaten to tear it apart.

    “It’s like hitting it with a hammer 10 million times a year,” Hylen said.

    Because of the various pressures acting on the horn, its design requires extreme attention to detail, down to the specific shape of the washers used. And as Fermilab is entering a precision era of neutrino experiments running at higher beam powers, the need for the horn engineering to be exact has only grown.

    “They are structural and electrical at the same time,” Zwaska said. “We go through a huge amount of effort to ensure they are made extremely precisely.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FNAL Icon
    Fermilab Campus

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

     
  • richardmitnick 6:28 am on August 23, 2016 Permalink | Reply
    Tags: , , , Neutrinos,   

    From SURF: “Study improves blasting designs” 

    SURF logo
    Sanford Underground levels

    Sanford Underground Research facility

    August 22, 2016
    Constance Walter

    1
    This image illustrates the sequence in which a blast round happens. Prior to a blast, the pattern is marked on the face of the rock. The round begins at the center and the hole increases in size with a series of boxes and diamonds. The holes marked in red after the final diamond, called field holes, round out the arch shape of the drift. Production holes along the sides and top of the drift complete the arch. Lastly, the lifters on the ground level out the floor of the drift. Credit: Matt Kapust

    The Long-Baseline Neutrino Facility and associated Deep Underground Neutrino Experiment (LBNF/DUNE) will include constructing facilities above and below ground at Sanford Lab in Lead, S.D., and Fermilab in Batavia, Ill.

    FNAL LBNF/DUNE from FNAL to SURF
    “FNAL LBNF/DUNE from FNAL to SURF

    But it is on the 4850 Level of Sanford Lab that construction could have the greatest impact on current experiments.

    Work at Sanford Lab includes excavating three large caverns on the 4850 Level: two that will house neutrino detectors filled with 70,000 tons of liquid argon, and one that will house utilities. Approximately 800,000 tons of rock will be removed. To understand the impacts such an excavation will have on existing experiments, the LBNF project conducted a blast vibration study.

    “We were primarily interested in how the blast energy moves through both the rock and the air in existing spaces to assess the potential impact on other experiments,” said Tracy Lundin LBNF Conventional Facilities project manager.

    “The different collaborations, including those with the Majorana Demonstrator, the Black Hills State University Underground Campus, and CASPAR (Compact Accelerator System for Performing Astrophysical Research) had concerns about the excavation and its potential impact on their experiments,” said Mike Headley, executive director of the South Dakota Science and Technology Authority. “The LBNF team has regularly consulted with the other collaborations on the blast vibration study plans and results, as well as approaches that can be taken to reduce the impacts the LBNF excavation might have on other experiments.”

    Preparation for the test blast required drilling a pattern of holes into the rock and filling most of them with explosives that get triggered in a specific timed sequence by detonators. A set of holes in the center of the pattern, called the burn cut, is left empty. The pattern is designed such that energy from the blasts in the outer holes propagates radially inward toward the burn cut.

    The initial study, done in December, successfully demonstrated how the energy moves through the rock mass. However, Lundin said, “it did not provide a complete understanding of air blast overpressures and our ability to manage impacts on existing facilities and experiments.”

    Two successive blasts done in March included a redesigned blast pattern, non-electronic detonators, and reinforced air control doors throughout the 4850 Level. Both were successful, informing the next LBNF blast designs. “Doing the study in two phases allowed us to make improvements to the blast design and to mitigate impacts on current experiments,” Lundin said.

    “The new blasting plans will allow LBNF to move forward as planned without harming other experiments,” Headley said.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition

    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 4:32 pm on August 18, 2016 Permalink | Reply
    Tags: Neutrinos, , Week 31 at the Pole   

    From IceCube: “Week 31 at the Pole” 

    icecube
    IceCube South Pole Neutrino Observatory

    1
    Christian Krueger, IceCube/NSF

    The igloo from last week is finally finished. What began as an afternoon project ended up taking an entire week (well, high winds were partly to blame). In the image above, you can see the igloo lit from within, and perhaps even discern that there are only few blocks missing to complete the ceiling. They had some fine auroras to watch while building the igloo, and once finished, they gathered inside for a group photo and a warm treat—not hot cocoa, but a Thai curry. With people inside, and with its low-profile, hidden-beneath-blankets entrance, the igloo can maintain an interior temperature above 0 ºF.

    The auroras were bountiful and varied in color last week, giving a nice purple show across a large part of the sky on one night. That can’t be what IceCube winterover Christian is reacting to in the last image below, since not only is he indoors but there are no unblocked windows to the outdoors that he could be looking through. What is it then? He is reacting to an elephant hiding in the janitor’s room—or “acting,” we should say, as it’s all part of shooting a short film for the Winter International Film Festival. Quite convincing, and a great teaser for their film!

    2
    Christian Krueger, IceCube/NSF

    3
    Christian Krueger, IceCube/NSF

    4
    South Pole WIFF Team/NSF

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    ICECUBE neutrino detector
    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 11:26 am on August 9, 2016 Permalink | Reply
    Tags: , , Neutrinos,   

    From FNAL: “LBNF/DUNE update: Much more than a hole in the ground” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

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

    August 1, 2016
    Chris Mossey

    Another few months have flashed by, and it’s time for a quick status update from the LBNF/DUNE project. Since my last update in May, the LBNF team has been very focused on getting in place the “CM/GC” contract, the contract that we plan to use to accomplish the conventional facilities construction at the project’s far site. CM/GC is short for “construction manager/general contractor” contract. I admit it doesn’t exactly roll off the tongue.

    Using a CM/GC contract will be a first for Fermilab and represents a novel approach to address some of the project’s unique challenges at the far site.

    Of course, there will be a substantial amount of excavation (800,000 tons of rock!) to create the three massive caverns and supporting drifts that will support the DUNE experiment.

    1
    Under Secretary Franklyn Orr and team visit the drift that will lead into the LBNF/DUNE site. Photo credit: Walter Wenning.

    But even more of a challenge will be coordinating all of the underground construction work. In addition to the excavation, tasks such as building two cryogenic systems, erecting four six-story-tall cryostats, installing the neutrino detectors and filling the cryostats with liquid argon (all through a mile-deep shaft that, at its largest is only 5 feet wide by nearly 13 feet deep).

    That’s where the “CM” in “CM/GC” comes in. A key role of the selected contractor will be to provide construction management services to help the project complete final design and then, when our partners are ready, help coordinate installation of the massive cryostats, cryo systems and neutrino detectors.

    We’ve made a lot of progress in getting the CM/GC contractor on board in the past two months. In late June, we received official approval from the DOE Office of Science’s senior contracting official to use the CM/GC acquisition strategy.

    We put the contract “on the street” the next day (actually, we just posted it on the federal contract opportunities website) to enable potential contractor partners to begin to review the contract, plans and specs.

    Then, a couple of weeks ago, our procurement team organized a preproposal meeting out near the site in South Dakota. We were pleased that more than 50 people showed up from a variety of contracting and construction management firms to participate in the meeting and get a firsthand sense of the work by touring underground at Sanford Lab.

    SURF logo

    FNAL DUNE Argon tank at SURF
    Argon tank at SURF

    Chris Mossey is the Fermilab deputy director for LBNF.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FNAL Icon
    Fermilab Campus

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

     
  • richardmitnick 2:56 pm on August 8, 2016 Permalink | Reply
    Tags: , , Neutrinos, ,   

    From ICL: “Evidence mounts that neutrinos are the key to the universe’s existence” 

    Imperial College London
    Imperial College London

    06 August 2016
    Hayley Dunning

    T2K Experiment
    T2K map
    T2K Experiment; T2K map

    1
    The T2K near detector. No image credit

    New experimental results show a difference in the way neutrinos and antineutrinos behave, which could explain why matter persists over antimatter.

    The results, from the T2K experiment in Japan, show that the degree to which neutrinos change their type differs from their antineutrino counterparts. This is important because if all types of matter and antimatter behave the same way, they should have obliterated each other shortly after the Big Bang.

    So far, when scientists have looked at matter-antimatter pairs of particles, no differences have been large enough to explain why the universe is made up of matter – and exists – rather than being annihilated by antimatter.

    Neutrinos and antineutrinos are one of the last matter-antimatter pairs to be investigated since they are difficult to produce and measure, but their strange behaviour hints that they could be the key to the mystery.

    Flavour change

    Neutrinos (and antineutrinos) come in three ‘flavours’ of tau, muon and electron, each of which can spontaneously change into the other as the neutrinos travel over long distances.

    The latest results, announced today by a team of researchers including physicists from Imperial College London, show more muon neutrinos changing into electron neutrinos than muon antineutrinos changing into electron antineutrinos.

    This difference in muon-to-electron changing behaviour between neutrinos and antineutrinos means they would have different properties, which could have prevented them from destroying each other and allow the universe to exist.

    To explore the (anti)neutrino flavour changes, known as osciallations, the T2K experiment fires a beam of (anti)neutrinos from the J-PARC laboratory at Tokai Village on the eastern coast of Japan.

    It then detects them at the Super-Kamiokande detector, 295 km away in the mountains of the north-western part of the country. Here, the scientists look to see if the (anti)neutrinos at the end of the beam matched those emitted at the start.

    Very intriguing

    The latest results were concluded from relatively few data points, meaning there is still a one in 20 chance that the results are due to random chance, rather than a true difference in behaviour. However, the result is still exciting for the scientists involved.

    Dr Morgan Wascko, international co-spokesperson for the T2K experiment from the Department of Physics at Imperial said: “This is an important first step towards potentially solving one of the biggest mysteries in science.

    “T2K is the first experiment that is able to study neutrino and antineutrino oscillation under the same conditions, and the disparity we have observed is, while not yet statistically significant, very intriguing.”

    Dr Yoshi Uchida, also from the Department of Physics at Imperial and a principal investigator at T2K, added: “More data is needed to prove conclusively that neutrinos and antineutrinos behave differently, but this result is an indication that neutrinos will continue to provide breakthroughs in our understanding of the universe.

    Upgrades to the equipment that produces (anti)neutrinos, as well as to the detector that measures them, are expected to add more data within the next decade, and determine whether the difference is in fact real.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 2:11 pm on August 8, 2016 Permalink | Reply
    Tags: , , Neutrinos, ,   

    From FNAL: “NOvA shines new light on how neutrinos behave” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

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

    August 8, 2016
    Media contact:
    Andre Salles, Fermilab Office of Communication, media@fnal.gov, 630-840-3351

    Science contacts:
    Mark Messier, Indiana University, NOvA co-spokesperson, messier@indiana.edu, 812-855-0236
    Peter Shanahan, Fermilab, NOvA co-spokesperson, shanahan@fnal.gov, 630-840-8378

    New result indicates that the flavor and mass correlation may be more complex than previously thought.

    Scientists from the NOvA collaboration have announced an exciting new result that could improve our understanding of the behavior of neutrinos.

    FNAL/NOvA experiment
    FNAL/NOvA experiment map

    FNAL NOvA Near Detector
    FNAL NOvA Near Detector

    Neutrinos have previously been detected in three types, called flavors – muon, tau and electron. They also exist in three mass states, but those states don’t necessarily correspond directly to the three flavors. They relate to each other through a complex (and only partially understood) process called mixing, and the more we understand about how the flavors and mass states connect, the more we will know about these mysterious particles.

    As the collaboration will present today at the International Conference on High Energy Physics in Chicago, NOvA scientists have seen evidence that one of the three neutrino mass states might not include equal parts of muon and tau flavor, as previously thought. Scientists refer to this as “nonmaximal mixing,” and NOvA’s preliminary result is the first hint that this may be the case for the third mass state.

    “Neutrinos are always surprising us. This result is a fresh look into one of the major unknowns in neutrino physics,” said Mark Messier of Indiana University, co-spokesperson of the NOvA experiment.

    The NOvA experiment, headquartered at the U.S. Department of Energy’s Fermi National Accelerator Laboratory, has been collecting data on neutrinos since February 2014. NOvA uses the world’s most powerful beam of muon neutrinos, generated at Fermilab, which travels through the Earth 500 miles to a building-size detector in northern Minnesota. NOvA was designed to study neutrino oscillations, the phenomenon by which these particles “flip” flavors while in transit.

    NOvA has been using the oscillations of neutrinos to learn more about their basic properties for two years. The NOvA detector is sensitive to both muon and electron neutrinos and can analyze the number of muon neutrinos that remain after traveling through the Earth and the number of electron neutrinos that appear during the journey.

    The data also show that the third mass state might have more muon flavor than tau flavor, or vice versa. The NOvA experiment hasn’t yet collected enough data to claim a discovery of nonmaximal mixing, but if this effect persists, scientists expect to have enough data to definitively explore this mystery in the coming years.

    “NOvA is just getting started,” said Gregory Pawloski of the University of Minnesota, one of the NOvA scientists who worked on this result. “The data sample reported today is just one-sixth of the total planned, and it will be exciting to see if this intriguing hint develops into a discovery.”

    2
    The NOvA experiment’s preliminary result shows an equal possibility that the third neutrino mass state is dominated by either muon or tau flavor. Image: NOvA collaboration.

    NOvA will take data with neutrinos and antineutrinos over the next several years. With both detectors running smoothly and Fermilab’s neutrino beam at full strength, the NOvA experiment is well positioned to illuminate many of the remaining neutrino mysteries.

    The NOvA experiment is funded by the U.S. Department of Energy Office of Science, the National Science Foundation and other institutions worldwide.

    For more information on NOvA, visit their website. To read a public presentation on this result, please visit this link.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FNAL Icon
    Fermilab Campus

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

     
  • richardmitnick 11:23 am on August 3, 2016 Permalink | Reply
    Tags: , , Neutrinos, ,   

    From SLAC: “Physicist Trio Amplifies SLAC Research on Mysterious Forms of Matter” 


    SLAC Lab

    August 2, 2016

    1
    Left: This image shows the remnant of Supernova 1987A, a star explosion detected in 1987, in three different wavelengths (radio, red; visible, green; X-ray, blue). Neutrinos released by supernovae and detected on Earth help researchers understand how stars die. Right: This artist’s impression shows the Milky Way galaxy inside a halo of dark matter (blue), an invisible substance that makes up 85 percent of all matter in the universe. Researchers search for unknown particles and forces related to dark matter. (ALMA/A. Angelich/NASA/ESA, ESO/L. Calçada)

    Elusive Neutrinos and Hypothetical ‘Dark Sector’ Particles Could Hold Answers to Cosmic Mysteries

    All material things appear to be made of elementary particles that are held together by fundamental forces. But what are their exact properties? How do they affect how our universe looks and changes? And are there particles and forces that we don’t know of yet?

    Questions with cosmic implications like these drive many of the scientific efforts at the Department of Energy’s SLAC National Accelerator Laboratory. Three distinguished particle physicists have joined the lab over the past months to pursue research on two particularly mysterious forms of matter: neutrinos and dark matter.

    Neutrinos, which are abundantly produced in nuclear reactions, are among the most common types of particles in the universe. Although they were discovered 60 years ago, their basic properties puzzle scientists to this date.

    Alexander Friedland, a senior staff scientist in SLAC’s Elementary Particle Physics Theory Group, works on techniques that pave the way for future analyses of neutrino bursts from supernovae. Studying the details of these powerful star explosions helps scientists understand how dying stars spit out chemical elements into deep space.

    Natalia Toro and Philip Schuster, associate professors of particle physics and astrophysics at SLAC, look for something even more enigmatic. They develop ideas for experiments that search for hidden particles and forces linked to dark matter, an invisible form of matter that is five times more prevalent than ordinary matter.

    “Alex, Natalia and Philip are significant additions to the SLAC family, whose outstanding expertise tremendously strengthens our research in areas of national priority,” says JoAnne Hewett, head of the lab’s Elementary Particle Physics Division. Neutrino physics and dark matter research are among the five science drivers for U.S. particle physics identified in 2014 by the Particle Physics Project Prioritization Panel. Neutrino research also ranked high in the 2015 long-range plan for nuclear science issued by the Nuclear Science Advisory Committee.

    Neutrinos from Across the Country and from Across the Galaxy

    One of the major neutrino projects with SLAC involvement is the international Deep Underground Neutrino Experiment (DUNE) at the planned Long-Baseline Neutrino Facility (LBNF) – the world’s flagship neutrino experiment for the coming decade and beyond.

    FNAL LBNF/DUNE from FNAL to SURF
    FNAL LBNF/DUNE from FNAL to SURF

    Researchers will send a neutrino beam produced at Fermi National Accelerator Laboratory in Illinois to the Sanford Underground Facility in South Dakota.

    SURF logo

    After travelling 800 miles through the Earth, some of these neutrinos will be detected by the DUNE Far Detector, which will eventually consist of four 10,000-ton modules of liquid argon located 4,850 feet underground.

    FNAL DUNE Argon tank at SURF
    FNAL DUNE Argon tank at SURF

    The ultrasensitive neutrino “eye” will measure how the three known types of neutrinos, called flavors, and their antiparticles morph from one into another during their underground journey. This study will provide crucial insights into the relative masses of neutrino flavors and the possibility that antineutrinos behave differently than neutrinos, which could potentially help explain why the universe is made of matter rather than antimatter. The experiment will also follow up on hints that there may be more than three neutrino flavors in nature.

    “To help DUNE reach its full potential, my work addresses a number of fundamental questions,” says Friedland, SLAC’s first neutrino theorist, who joined the lab in the summer of 2015. “How can additional neutrinos be incorporated into our theories? Are there also additional forces? Is there a link between neutrinos and dark matter? How do neutrinos interact with atomic nuclei in the detector material?”

    In addition to neutrinos from Fermilab, DUNE will also be able to detect very brief neutrino bursts from supernovae – powerful explosions of massive stars with cores that can no longer resist gravity and collapse to form dense neutron stars.

    “Such a burst should be an exquisite probe of neutrino properties,” Friedland says. “Our goal is to understand how to read the signal and optimize our detector for it.”

    Supernova explosions are important events in the universe. They inject chemical elements, synthesized inside stars over their lifetimes, into space, including crucial elements of life. Friedland hopes that DUNE’s data will reveal never-before-seen details in the related neutrino bursts that could open a window into the processes inside dying stars.

    “Our calculations show that those neutrino signals have a certain time structure that is linked to what’s going on in the star,” he says. “Measuring these minute details could help us understand the different stages of a supernova, from the collapse of the star’s core to the outward propagation of powerful shock waves.”

    Such detailed analysis can only be done by looking at neutrinos. Unlike other particles, which frequently interact with their surroundings on their way out of the star and therefore carry the imprint of this complicated environment, neutrinos stream out nearly undisturbed and deliver direct information about the processes in which they were set free.

    “Supernovae go off without warning, and detectable ones don’t occur very often,” says Friedland, who co-leads the DUNE supernova working group. “Although the next supernova neutrino burst may be a decade or more away, what will be seen then is affected by crucial decisions about the detector design made now. My job is to make sure that we’ll be prepared.”

    SLAC provides a unique environment for the pursuit of this line of research, according to Friedland. “The lab is building a strong neutrino program, with experimentalists and theorists working closely together,” he says. “It also unites a number of disciplines under one roof that stimulate and complement each other, from particle physics to astrophysics to computing.”

    Before coming to SLAC, Friedland was at Los Alamos National Laboratory, first as a Richard P. Feynman Fellow and then as a staff scientist. He received his doctorate in physics from the University of California, Berkeley in 2000 and pursued postdoctoral research at the Institute for Advanced Study in Princeton, New Jersey from 2000 to 2002. In addition to neutrinos, Friedland’s studies look into unknown ultraweak forces in nature, extra dimensions beyond space and time and the effect of postulated particles on the evolution of stars.

    Searching for ‘Light Dark Matter’

    Another burning question researchers around the world are yearning to answer is: What is dark matter? With 85 percent of all matter in the universe being dark, this invisible substance has tremendous influence on how the cosmos evolves. Although scientists know that dark matter exists because it gravitationally pulls on ordinary matter, they have yet to find out what it is made of.

    At SLAC, Natalia Toro and Philip Schuster search for entire dark sectors of hypothetical particles and forces that could be linked to dark matter.

    “We work on a number of small-scale experiments that have a real shot at discovering what dark matter is or what it isn’t,” Schuster says. “Unlike most dark matter searches, which focus on rather massive particles, we look for much lighter ones, in a mass range that is surprisingly unexplored.”

    The researchers participate in two experiments that hunt for light dark matter at the Thomas Jefferson National Accelerator Facility in Virginia: the Heavy Photon Search (HPS), for which the scientists developed the theoretical framework, and the A Prime Experiment (APEX), which they co-lead. Both experiments hope to catch a glimpse of dark photons – hypothetical carriers of a new force – that could potentially be produced when powerful electron beams slam into a target. Toro and Schuster are also members of a collaboration that proposed a third experiment at Jefferson Lab to search for dark matter, the Beam Dump Experiment (BDX).

    Similar searches could also be done at SLAC once the upgrade to the lab’s Linac Coherent Light Source (LCLS) X-ray laser, a DOE Office of Science User Facility, is complete.

    SLAC LCLS-II line
    SLAC LCLS-II

    The future LCLS-II will produce X-rays from a rapid sequence of electron bunches – up to a million per second – that will fly through the facility’s linear particle accelerator.

    “We’re developing ideas for an experiment that would use the dark current of LCLS-II’s electron beam,” Toro says. “This is a small number of unused electrons in between the main bunches that we could extract and shoot into targets for light dark matter searches.”

    A proposal based on this concept is the Light Dark Matter Experiment (LDMX), whose young collaboration is led by researchers from the University of California, Santa Barbara, the University of Minnesota and SLAC.

    At the moment, the parasitic use of LCLS-II is only an idea, but Toro and Schuster have already teamed up with members of SLAC’s Accelerator Directorate to think about how these experiments could be designed and, most importantly, operated without interfering with X-ray laser operations. Together they are exploring the possibility for a future facility for Dark Sector Experiments at LCLS-II (DASEL).

    “The lab has a unique culture of vibrant collaborations,” Toro says. “It creates an ideal environment to follow through with our projects from beginning to end. Here we can establish the theoretical foundation, work on the engineering aspects and turn them into successful experiments, all in one place.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    SLAC Campus
    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.
    i1

     
  • richardmitnick 12:10 pm on August 2, 2016 Permalink | Reply
    Tags: , , Neutrinos, NOvA experiment   

    From FNAL: “A new hunt for sterile neutrinos with NOvA” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

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

    July 29, 2016
    Adam Aurisano
    Gareth Kafka

    FNAL/NOvA experiment
    NOvA map

    2
    NOvA predicted it would observe 84 neutral-current events if there are no oscillations between active and sterile neutrinos. The colored histograms show the breakdown of the predicted signal and background events as a function of the energy deposited in the detector. The black data points show the data that was observed in the NOvA far detector. There is no evidence for oscillations into sterile neutrinos. No image credit.

    3
    NOvA found no evidence for oscillations between active and sterile neutrinos based on the events it observed. This translates into limits on mixing angles governing the active to sterile oscillations, similar to those that govern the oscillations between the standard active neutrinos. Sterile oscillations would require nonzero values of either θ24 or θ34, so the NOvA measurement rules out large values of these angles. No image credit.

    For 86 years after they were proposed by Wolfgang Pauli, and 60 years after they were discovered by Clyde Cowan and Frederick Reines with an experiment aptly named Project Poltergeist, neutrinos have remained the most elusive ghosts of particle physics.

    One of the great scientific discoveries of the last century, and one of the first indications found of physics beyond the Standard Model, is that neutrinos oscillate. That is, if a neutrino starts off as one flavor, after traveling some distance, it is possible it will be detected as a different flavor.

    Most experiments measuring neutrino oscillation have seen results consistent with the premise that there are only three of these neutrino flavors – electron, muon and tau. However, results from a few experiments, such as LSND at Los Alamos National Laboratory and Fermilab’s MiniBooNE, can be explained by neutrino oscillations only if we include one or more new neutrino flavors different from the three familiar ones.

    4
    LSND experiment, Los Alamos Laboratory

    FNAL/MiniBooNE
    FNAL/MiniBooNE

    Neutrinos interact through the weak force, and precision measurements with the Large Electron-Positron collider (LEP, the LHC predecessor at CERN) showed that the weak force interaction can couple only with three neutrino flavors. That means that any extra neutrino flavors must not participate in these weak interactions, and so we call these extra hypothetical particles sterile neutrinos. Because they have virtually no interactions with matter, these sterile neutrinos are even harder to detect than the neutrinos we know. They are truly a ghost particle’s ghost!

    There are two weak interaction channels for neutrinos: charged-current and neutral-current interactions. Charged-current interactions involve a neutrino, a W boson, and a charged lepton (electron, muon or tau). These interactions are sensitive to the familiar “active” neutrino flavors and hence to oscillations between those flavors. Neutral-current interactions involve a neutrino and a Z boson, without the emerging charged lepton, so they are blind to the active neutrino flavor and hence blind to oscillations between those flavors.

    Measuring neutral-current neutrino interactions lets one measure the overall number of neutrinos of any active flavor, regardless of whether they have changed flavor while traveling. Neutral-current neutrino interactions therefore offer a prime avenue for determining whether oscillations between the three active neutrinos and sterile neutrinos are occurring. If so, those oscillations would lead to a partial deficit in the total number of active neutrino interactions, and we would see that telltale signature in our measurement of the number of neutral-current interactions. This deficit is something we can look for with a neutrino experiment like NOvA.

    NOvA is a two-detector experiment using an incredibly intense source of neutrinos produced by the Main Injector particle accelerator at Fermilab. NOvA has a small detector on site at Fermilab, one that we use to measure the rate of neutral-current neutrino interactions happening before any oscillations take place. It also has a second detector located 810 kilometers away that measures the neutrinos after they may have oscillated into sterile flavors.

    The powerful source of neutrinos it measures means that NOvA samples a very high rate of neutrino interactions among the global landscape of neutrino experiments and also observes a large number of neutral-current neutrino events.

    The NOvA detectors have been collecting data since summer 2014 and, so far, NOvA has analyzed 16 percent of the total data it expects to collect. At the recent Neutrino 2016 conference, NOvA released the first results for its search for neutral-current oscillations. It predicted to see 84 of these neutral-current neutrino events and observed 95, as you can see in the first plot above. This of course means that no deficit of events was observed, showing no evidence for oscillations into sterile neutrinos. Instead, we can use these data to place constraints on the parameters that would govern oscillations into sterile neutrinos. The limits NOvA sets on how strongly a new sterile neutrino flavor could mix with the three active neutrino flavors are shown in the second plot.

    NOvA has collected only a small fraction of data from its design goal, but it is already making competitive measurements within the global environment of sterile neutrino oscillations. It will be very exciting to see how NOvA improves the world’s understanding of sterile neutrino oscillations in the coming years.

    Gavin Davies of Indiana University will present these new NOvA results at Fermilab during the Joint Experimental-Theoretical Seminar on Friday, July 29.

    Adam Aurisano is a postdoc at the University of Cincinnati. Gareth Kafka is a graduate student at Harvard University.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FNAL Icon
    Fermilab Campus

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

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
Follow

Get every new post delivered to your Inbox.

Join 599 other followers

%d bloggers like this: