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  • richardmitnick 10:28 am on September 23, 2016 Permalink | Reply
    Tags: , , Neutrinos, , , PTOLEMY laboratory, Tritium   

    From PPPL: “Intern helped get robotic arm on PPPL’s PTOLEMY experiment up and running” 


    PPPL

    September 22, 2016
    Jeanne Jackson DeVoe

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    PPPL intern Mark Thom with a device containing a robotic arm that will be used with PPPL’s PTOLEMY experiment, behind him. (Photo by Elle Starkman/PPPL Office of Communications)

    Deep in a laboratory tucked away in the basement of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL), intern Mark Thom punched commands into a computer as two other students checked a chamber where a silver robotic arm extended from a small port.

    The arm will allow scientists studying neutrinos that originated at the beginning of the universe to load a tiny amount of nuclear material into the device while still maintaining a vacuum in the PTOLEMY laboratory.

    Thom, along with high school interns Xaymara Rivera and Willma Arias de la Rosa, worked closely with Princeton University physicist Chris Tully and PPPL engineers to get the robotic arm moving again. The crucial device will load tritium, a radioactive isotope of hydrogen, into PTOLEMY, the Princeton Tritium Observatory for Light, Early Universe Massive Neutrino Yield.

    Tritium can capture Big Bang neutrinos and release them with electrons in radioactive decay. The neutrinos can provide a tiny boost of energy to the electrons, which PTOLEMY is designed to precisely measure in the darkest, coldest conditions possible. It is funded by the Mark Simons Foundation and the John Templeton Foundation.

    “For me it was just amazing that I actually got onto that project,” Thom said. “It’s exactly the kind of thing I thought I would like to do, being an engineer working on a high-energy physics project.”

    The robotic arm, together with the portable container and the computer program to operate it, were recycled from another experiment when Thom and fellow interns Rivera and Arias de la Rosa began the project. Thom was responsible for making the arm operational and altering it so it would fit PTOLEMY.

    Handling delicate materials

    Tully said the device can safely handle very delicate radioactive materials from DOE’s Savannah River National Laboratory. Without the device, scientists would have to shut down PTOLEMY completely twice a day to change the tritium sample, he said. Maintaining a vacuum in PTOLEMY is also necessary for the extremely sensitive sensors that measure the energy spectrum of the electrons emitted from the tritium to function properly.

    To make the robotic arm function again, Thom had to analyze why the coding was failing, which meant learning the code for the machine. He had to learn an unfamiliar program and then rewrite it to redirect the arm to handle tritium samples, without having worked on a device of that kind before, Tully said.

    The students encountered a setback when the arm stopped working. At first, they thought the device would need a new motor, which would cost $20,000. It turned out that the culprit was a circuit that would cost just a few dollars to replace. While Tully fixed the computer, Thom took the arm apart and researched how to install magnetic shielding around the motors and sketched a design for that shielding, Tully said. “Mark was quite amazing,” he said. “I was very impressed with him.”

    Thom also designed a cover for one of the ports that would need to be sealed for the robotic arm to work. Rivera and Arias de la Rosa helped him operate and test the robotic arm and wrote procedures for running it. Thom and the other interns also worked with PPPL engineers Charles Gentile and Mike Mardenfeld, along with senior mechanical technician Andy Carpe and lead technician Jim Taylor.

    Gentile, who supervised Thom and other engineering interns, said Thom was one of the best interns he has seen in 25 years of supervising more than 200 interns. “He’s an excellent mechanical engineer,” Gentile said. “He was a hard worker and he came up with innovative solutions to problems.”

    The arm connects to PTOLEMY through two ports equipped with valves. One valve connects to the experiment. The other connects to a loading chamber where scientists can insert a tiny sample of tritium on a graphene base.

    Researchers would create a vacuum in the loading chamber and attach it to the vacuum chamber of PTOLEMY. The robotic arm could then collect the tritium and graphene sample and deposit it into PTOLEMY. Researchers would next retract the arm and close the valve connecting it to PTOLEMY.

    Following parents’ footsteps

    Thom, who is in his final year of master’s degree work at Howard University, is from Trinidad. The son of two engineers, he considered becoming a physician and briefly flirted with the idea of being an actor or music producer before choosing to follow in his parents’ footsteps.

    Thom studied engineering as an undergraduate at Howard. He learned about the internship when Andrea Moten, PPPL acting director of human resources, and engineer Atiba Brereton met him at National Laboratory Day at Howard University in February. The two passed Thom’s resume along to Gentile as a candidate for the engineering apprenticeship program.

    The graduate student recently celebrated his one-year anniversary with his wife, Sydney, who is also an engineer and is currently teaching at a Kipp DC Middle School in Washington, D.C. Thom commuted to Washington every weekend on Friday nights to see her and then headed back to New Jersey on Monday mornings. “It was challenging at first,” he said. “But after a while I got accustomed to it and I actually began to appreciate those drives because it gave me some time to think.”

    Thom said he enjoyed the laid-back atmosphere at PPPL. He was surprised when Gentile told him he was overdressed on his first day. But he most enjoyed talking to researchers about their work. “I met some really cool people – a bunch of physicists whom I was able to have certain conversations with, just talking about abstract theories. That’s the kind of conversation I enjoy,” Thom said. “Being able to interact with people like that in that atmosphere was really enjoyable.”

    The internship gave him a better idea of possible careers as he prepares to graduate, Thom said. “I had a limited view of the engineering world prior to going into this work,” he said. “But now I have a better idea of the kind of environment I’d like to be in, so it gives me idea of what I should do to prepare for that environment.”

    See the full article here .

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    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University. PPPL, on Princeton University’s Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

     
  • richardmitnick 10:38 am on September 22, 2016 Permalink | Reply
    Tags: , Clint Wiseman SCGSR Award winner, , Neutrinos,   

    From SURF: “SCGSR Award opens door to new research” 

    SURF logo
    Sanford Underground levels

    Sanford Underground Research facility

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    Clint Wiseman. Credit: Constance Walter

    In an article he wrote for the University of South Carolina physics newsletter, Clint Wiseman said, “For the last three years I’ve been living under a rock with neutrinos on my mind.” The University of South Carolina (USC) graduate student was referring to his work on the Majorana Demonstrator Project, which is located on the 4850 Level of Sanford Lab. But all of that is about to change.

    Majorana Demonstrator Experiment
    Majorana Demonstrator Experiment

    Wiseman recently learned he had received a Department of Energy Office of Science Graduate Student Research (SCGSR) award. In January, he heads to Los Alamos National Laboratory in New Mexico to work on his Ph.D. project for six months.

    “My work with Majorana gave me confidence that I could get the award,” he said. “Still, I was speechless. I was flabbergasted. I was elated.”

    Wiseman has been involved in almost every aspect of the Majorana experiment: construction, commissioning, operation, and data analysis. “One of my colleagues told me that he’s done everything on Majorana incorrectly and correctly. That applies to me also,” Wiseman said. Still, he’s learned a great deal.

    “Clint is highly motivated and talented,” said Vince Guiseppe, an assistant professor of physics at USC and Wiseman’s advisor. “With this SCGSR award, he has the added opportunity to expand upon his dissertation work and gain experience at a National Laboratory.”

    To be considered for the SCGSR, graduate students must submit a proposal that is in line with their dissertation. Wiseman’s thesis focuses on cosmic ray and solar axion studies with Majorana. The project he proposed to DOE focuses on ways to improve shielding of germanium detectors.

    In the search for a rare form of radioactive decay, called neutrinoless double-beta decay, scientists use special shielding to eliminate background noise from cosmic rays. The Majorana experiment operates within a vacuum: the detectors are placed in a copper cryostat and surrounded by a six-layered shield. Conversely, the German experiment GERDA has an active shield: the detectors are submerged in liquid argon.

    “Both have advantages and disadvantages,” Wiseman said. So, he is proposing something that has never been done: operating a germanium detector in a gas environment.

    Could that remove problems with current shielding environments? Wiseman doesn’t know, but through his work at Los Alamos, he hopes to find out.

    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 11:39 am on September 20, 2016 Permalink | Reply
    Tags: A Day in the Life of Engineering Physicist Linda Bagby, , , Neutrinos,   

    From FNAL: Women in STEM – “A Day in the Life of Engineering Physicist Linda Bagby” Video 

    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.

    Linda Bagby keeps Fermilab’s neutrino experiments grounded. As an engineering physicist and electrical coordinator for Fermilab’s short-baseline neutrino program, she integrates the electronic subsystems into an experiment where all the electronics work together. You might find her cheerfully fielding questions in Wilson Hall, taking painstaking measurements at one of the detector sites or meticulously inspecting equipment at a test site.

    See the full article here .

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    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 12:17 pm on September 17, 2016 Permalink | Reply
    Tags: , , Neutrinos, Northern Illinois University,   

    From NIU via FNAL: “NIU joins DUNE project” 

    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.

    2
    NorthernStar

    3
    Northern Illinois University

    Sep 15, 2016
    Samantha Malone

    4

    DeKALB | Dan Boyden, third year physics graduate, is hoping to be sent to Switzerland to work hands-on for DUNE, an international particle experiment including more than 140 labs and universities across 27 countries.

    DUNE, which stands for Deep Underground Neutrino Experiment, aims to reveal things about the universe, like why the world has more matter than antimatter. NIU was asked to join the project which is being led by Associate Physics Professor Vishnu Zutshi and Physics Professor Michael Eads.

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

    Boyden got involved in the experiment when a friend told him that his professor was looking for help on the project. Boyden said he saw the project as a great opportunity to network and get hands-on experience. Networking is vital in his field, and working on DUNE provides the opportunity to connect with many people, Boyden said.

    Zutshi and Eads approached DUNE and were later asked to join the experiment as a result of Zutshi’s knowledge on the topics the experiment explores, like photon detectors.

    “The point to make is this is a new effort here at NIU,” Eads said. “We’re hoping to ramp this up and get more people involved in the near future.”

    The DUNE project hopes to measure the properties of neutrinos, a nearly neutral fundamental particle of the universe, as they travel. There are three types of neutrinos, and as they travel, they can change from one type to another. This process is called oscillation, Physics Professor David Hedin said.

    NIU’s task for DUNE is to build and test the photon detector systems that will measure the neutrino oscillations as they travel. Boyden was assigned the task of testing these systems, which he said were essentially light detectors.

    “I’m performing the tests that are needed for NIU to perform their part,” Boyden said. “Right now, we’ve been mostly just measuring background noise and things like that associated with electronics.”

    While Boyden is the only student involved in the project, Eads said he hopes to provide opportunities for more graduate and undergraduate physics students in the future.

    The photon detectors Boyden is working with will tell scientists on the DUNE team when a neutrino changes, which could allow them to determine the probability of such action, Eads said. Determining that probability could tell scientists why the universe has more matter than antimatter, which allows people to exist, Hedin said.

    “We still have a big question mark about what caused the matter-antimatter difference,” Hedin said. “The guess right now is that the matter-antimatter difference in our universe is in the type of particles like electrons and neutrinos.”

    Hedin, Eads and Zutshi work at Fermilab as visiting scientists. Fermilab and NIU have a partnership that Hedin said gives students and faculty great opportunities. Eads said the close proximity NIU has to Fermilab enhances that.

    Fermilab will house the proton accelerator and produce the neutrinos that will be measured in the DUNE experiment.

    “So what the DUNE project is all about is studying neutrinos,” Eads said. “Neutrinos are one of the particles that make everything up, and we’re just trying to better understand how neutrinos work and what their properties are.”

    DUNE plans to do this by using the world’s largest neutrino beam to shoot the neutrinos from Fermilab, Outer Ring Road, located in Batavia, to Sanford Underground Research Lab in Lead, South Dakota. As the neutrinos travel underground, DUNE will be monitoring their properties and looking for a change in the type of neutrino.

    SURF logo
    surf-dune-lbnf-caverns-at-sanford-lab
    DUNE at SURF

    Because of the massive scale of the project, the first beam is not expected to be launched until 2026, but NIU has already begun work on its contributions.

    “It’s one of those fun research things where it’s not immediately clear how useful it’s [going to] be,” Eads said. “But if you understand the universe better, then it has to be good for something.”

    See the full article here .

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    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 1:53 pm on September 9, 2016 Permalink | Reply
    Tags: , , , Confirming The Big Bang's Last Great Prediction, Cosmic Neutrinos Detected, , , Neutrinos   

    From Ethan Siegel: “Cosmic Neutrinos Detected, Confirming The Big Bang’s Last Great Prediction” 

    From Ethan Siegel

    Sep 9, 2016

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    The Big Bang timeline of the Universe. Cosmic neutrinos affect the CMB at the time it was emitted, and physics takes care of the rest of their evolution until today. Image credit: NASA / JPL-Caltech / A. Kashlinsky (GSFC).

    The Big Bang, when it was first proposed, seemed like an outlandish story out of a child’s imagination. Sure, the expansion of the Universe, observed by Edwin Hubble, meant that the more distant a galaxy was, the faster it receded from us. As we headed into the future, the great distances between objects would continue to increase. It’s no great extrapolation, then, to imagine that going back in time would lead to a Universe that was not only denser, but thanks to the physics of radiation in an expanding Universe, hotter, too. The discovery of the cosmic microwave background [CMB] and the cosmic light-element background, both predicted by the Big Bang, led to its confirmation.

    CMB per ESA/Planck
    CMB per ESA/Planck

    But last year, a leftover glow unlike any other — of neutrinos — was finally seen. The final, elusive prediction of the Big Bang has finally been confirmed. Here’s how it all unfolded.

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    An illustration of the concept of Baryonic Acoustic Oscillations, which detail how large scale structure forms from the time of the CMB onward. This is also impacted by relic neutrinos. Image credit: Chris Blake & Sam Moorfield.

    Seventy years ago, we had taken fascinating steps forward in our conception of the Universe. Rather than living in a Universe governed by absolute space and absolute time, we lived in one where space and time were relative, depending on the observer. We no longer lived in a Newtonian Universe, but rather one governed by general relativity, where matter and energy cause the fabric of spacetime itself to curve. And thanks to the observations of Hubble and others, we learned that our Universe was not static, but rather was expanding over time, with galaxies getting farther and farther apart as time went on. In 1945, George Gamow made perhaps the greatest leap of all: the great leap backwards. If the Universe were expanding today, with all the unbound objects receding from one another, then perhaps that meant that all those objects were closer together in the past. Perhaps the Universe we live in today evolved from a denser state long ago. Perhaps gravitation has clumped and clustered the Universe together over time, while it was more even and uniform in the distant past. And perhaps  — since the energy of radiation is tied to its wavelength – that radiation was more energetic in the past, and hence the Universe was hotter long ago.

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    How matter and radiation dilute in an expanding Universe; note the radiation’s redshift to lower and lower energies over time. Image credit: E. Siegel.

    And if this were the case, it brought up an incredibly interesting set of events as we looked farther and farther back into the past:

    There was a time before large galaxies formed, where only small proto-galaxies and star clusters had come to be.
    Before that, there was a time before gravitational collapse had formed any stars, and all was dark: just primeval atoms and low-energy radiation.
    Prior to that, the radiation was so energetic that it could knock electrons off of the atoms themselves, creating a high-energy, ionized plasma.
    Even earlier than that, the radiation reached such levels that even atomic nuclei would be blasted apart, creating free protons and neutrons, and forbidding the existence of heavy elements.
    And finally, at even earlier times, the radiation would have so much energy that — through Einstein’s E = mc^2  —  matter-and-antimatter pairs would spontaneously be created.

    This picture is part of what’s known as the hot Big Bang, and it makes a whole slew of predictions.

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    An illustration of the cosmic history/evolution of the Universe since the inception of the Big Bang. Illustration: NASA/CXC/M.Weiss.

    Each one of these predictions, like a uniformly expanding Universe whose expansion rate was faster in the past, a solid prediction for the relative abundances of the light elements hydrogen, helium-4, deuterium, helium-3 and lithium, and most famously, the structure and properties of galaxy clusters and filaments on the largest scales, and the existence of the leftover glow from the Big Bang — the cosmic microwave background — has been borne out over time. It was the discovery of this leftover glow in the mid-1960s, in fact, that led to the overwhelming acceptance of the Big Bang, and caused all other alternatives to be discarded as non-viable.

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    Image credit: LIFE magazine, of Arno Penzias and Bob Wilson with the Holmdel Horn Antenna, which detected the CMB for the first time.

    But there was another prediction we haven’t talked about much, because it was thought to be untestable. You see, photons — or quanta of light — aren’t the only form of radiation in this Universe. Back when all the particles are flying around at tremendous energies, colliding into one another, creating and annihilating willy-nilly, another type of particle (and antiparticle) also gets created in great abundance: the neutrino. Hypothesized in 1930 to account for missing energies in some radioactive decays, neutrinos (and antineutrinos) were first detected in the 1950s around nuclear reactors, and later from the Sun, from supernovae and from other cosmic sources. But neutrinos are notoriously hard to detect, and they’re increasingly hard to detect the lower their energies are.

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    The energy/flux spectrum of the Big Bang’s leftover glow: the cosmic microwave background. Image credit: COBE / FIRAS, George Smoot’s group at LBL.

    That’s a problem, and it’s a big problem for cosmic neutrinos in particular. You see, by time we come to the present day, the cosmic microwave background (CMB) is only at 2.725 K, less than three degrees above absolute zero. Even though this was tremendously energetic in the past, the Universe has stretched and expanded by so much over its 13.8 billion year history that this is all we have left today. For neutrinos, the problem is even worse: because they stop interacting with all the other particles in the Universe when it’s only about one second after the Big Bang, they have even less energy-per-particle than the photons do, as electron/positron pairs are still around at that time. As a result, the Big Bang makes a very explicit prediction:

    There should be a cosmic neutrino background (CNB) that is exactly (4/11)^(1/3) of the cosmic microwave background (CMB) temperature.

    That comes out to ~1.95 K for the CNB, or energies-per-particle in the ~100–200 micro-eV range. This is a tall order for our detectors, because the lowest-energy neutrino we’ve ever seen is in the mega-eV range.

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    Image credit: IceCube collaboration / NSF / University of Wisconsin, via https://icecube.wisc.edu/masterclass/neutrinos. Note the huge difference between the CNB energies and all other neutrinos.

    So for a long time, it was assumed that the CNB would simply be an untestable prediction of the Big Bang: too bad for all of us. Yet with our incredible, precise observations of the fluctuations in the background of photons (the CMB), there was a chance. Thanks to the Planck satellite, we’ve measured the imperfections in the leftover glow from the Big Bang.

    Initially, these fluctuations were the same strength on all scales, but thanks to the interplay of normal matter, dark matter and the photons, there are “peaks” and “troughs” in these fluctuations. The positions and levels of these peaks and troughs tells us important information about the matter content, radiation content, dark matter density and spatial curvature of the Universe, including the dark energy density.

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    The best fit of our cosmological model (red curve) to the data (blue dots) from the CMB. Image credit: Planck Collaboration: P. A. R. Ade et al., 2013, A&A, for the Planck collaboration.

    There’s also a very, very subtle effect: neutrinos, which only make up a few percent of the energy density at these early times, can subtly shift the phases of these peaks and troughs. This phase shift – if detectable — would provide not only strong evidence of the existence of the cosmic neutrino background, but would allow us to measure its temperature at the time the CMB was emitted, putting the Big Bang to the test in a brand new way.

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    The fit of the number of neutrino species required to match the CMB fluctuation data. Image credit: Brent Follin, Lloyd Knox, Marius Millea, and Zhen PanPhys. Rev. Lett. 115, 091301 — Published 26 August 2015.

    Last year, a paper [Physical Review Letters] by Brent Follin, Lloyd Knox, Marius Millea and Zhen Pan came out, detecting this phase shift for the first time. From the publicly-available Planck (2013) data, they were able to not only definitively detect it, they were able to use that data to confirm that there are three types of neutrinos — the electron, muon and tau species — in the Universe: no more, no less.

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    The number of neutrino species as inferred by the CMB fluctuation data. Image credit: Brent Follin, Lloyd Knox, Marius Millea, and Zhen PanPhys. Rev. Lett. 115, 091301 — Published 26 August 2015.

    What’s incredible about this is that there is a phase shift seen, and that when the Planck polarization spectra came out and become publicly available, they not only constrained the phase shift even further, but — as announced by Planck scientists in the aftermath of this year’s AAS meeting — they finally allowed us to determine what the temperature is of this Cosmic Neutrino Background today! (Or what it would be, if neutrinos were massless.) The result? 1.96 K, with an uncertainty of less than ±0.02 K. This neutrino background is definitely there; the fluctuation data tells us this must be so. It definitely has the effects we know it must have; this phase shift is a brand new find, detected for the very first time in 2015. Combined with everything else we know, we have enough to state that yes, there are three relic neutrino species left over from the Big Bang, with the kinetic energy that’s exactly in line with what the Big Bang predicts.

    Two degrees above absolute zero was never so hot.

    See the full article here .

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    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

     
  • richardmitnick 9:43 am on September 8, 2016 Permalink | Reply
    Tags: , , MINERvA, Neutrinos   

    From FNAL: “Providing precise neutrino measurements with MINERvA” 

    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.

    September 8, 2016
    Michelle Mo

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    The front face of the MINERvA detector sits in its underground home near the end of construction. This front face is no longer visible because of the helium target that was installed upstream. Photo: Reidar Hahn

    Imagine an atomic nucleus as racked up pool balls with little springs attached to each other and the neutrino beam as the cue ball. It’s pretty easy to see what happens if you hit the pool balls with very little energy (almost nothing happens) or a lot of energy (they all break apart). But scientists need to know what happens with neutrinos in that middle energy level.

    “Some of the energy goes into breaking springs, some goes into breaking apart pool balls. Some goes into ejecting pool balls with energy,” said MINERvA co-spokesperson Kevin McFarland, a researcher at the University of Rochester. “Because it’s such a complicated system — you’re getting a big nucleus full of lots of neutrons and protons bound together with springs — it’s really hard to look at what comes out and infer precisely what the energy of the neutrino was.”

    By better understanding how neutrinos interact with the matter all around us, researchers hope to improve our model of how physics — and the universe — works. The information can be used in simulations of other neutrino experiments to correct for the energy that isn’t seen in these interactions and to improve accuracy.

    This information is crucial both for current neutrino experiments such as NOvA and in preparation for upcoming neutrino oscillation experiments such as the Deep Underground Neutrino Experiment, or DUNE.

    FNAL/NOvA experiment
    FNAL/NOvA experiment map

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

    At the energies required for those projects, the components of the nucleus begin to break apart, producing a slew of different particles and complex data.

    “We’re making measurements that haven’t been measured ever before,” said Minerba Betancourt, postdoctoral researcher for MINERvA. “For example, there’s a channel called quasielastic, in which a neutrino interacts with the detector and produces a muon and a proton. For that type of neutrino interaction, there are not any measurements of iron or lead to scintillator ratios.”

    Making new neutrinos

    A lot has to happen to produce MINERvA data. The experiment uses Fermilab’s Main Injector accelerator, which produces protons at energies of over 120 times their rest masses. These protons smash into a carbon target in the NuMI beamline, producing particles called pions that then transform into the desired neutrinos.

    FNAL NUMI Tunnel project
    NuMI beamline

    Sooner or later, a tiny fraction of these neutrinos interact with nuclei in the detector and produce daughter particles. These particles leave the nucleus, causing interactions that produce light in the scintillator detector that scientists record and analyze.

    “Neutrinos are neutral, so they don’t have a charge. We can’t see them until they actually produce something,” said Daniel Ruterbories, a postdoctoral researcher for MINERvA. “All of a sudden, particles spontaneously appear.”

    MINERvA has a unique ability to study neutrinos with high precision, primarily because of its detector technology. Those detector components, called scintillator bars, are small. That means physicists can measure neutrino interactions in more detail than a typical neutrino detector, which has to be huge because it has to be located hundreds of miles away from the neutrino source.

    Moving forward, MINERvA will analyze higher-energy neutrinos. By taking data at about 6 GeV of energy instead of the previous 3 GeV, scientists will be able to study many more interactions in the detector.

    “We’re producing a large bucket of events,” Ruterbories said. “We should be able to really focus down and try to answer the questions of how these interactions occur.”

    See the full article here .

    Please help promote STEM in your local schools.

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    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 10:33 am on September 6, 2016 Permalink | Reply
    Tags: , , Neutrinos,   

    From FNAL: “LBNF/DUNE Update: Over another hurdle” 

    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.

    September 1, 2016
    Chris Mossey
    Chris Mossey is the Fermilab deputy director for LBNF.

    We received great news on Sept. 1: the LBNF/DUNE CD-3a milestone was approved by Under Secretary Lynn Orr, on behalf of the DOE’s Energy Systems Acquisition Advisory Board. This critical decision milestone is the culmination of a variety of independent cost, schedule, management, and technical reviews and represents DOE’s green light to begin the significant amount of conventional facilities work at Sanford Underground Research Facility necessary to support the DUNE experiment.

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

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

    Sanford Underground levels
    Sanford Underground levels

    And we are ready to get started! The CD-3a work will include the excavation of two caverns: one that will hold two of the four planned DUNE detectors; and one for utilities and cryogenic systems. The work will begin in earnest once Congress makes FY2017 funding available. We are pleased that DOE has already requested this funding through the President’s Budget Request and it is in the appropriations bills currently under consideration by the House and the Senate.

    We’ll keep you updated as the work proceeds. The first step will be to install the systems that will transport hundreds of thousands tons of rock to a surface location. This preparatory work is planned to start in 2017. The major excavation for the first two DUNE neutrino detectors and related utility systems is planned to begin in the fall of 2018.

    As I mentioned in my last update, we’ve already begun the process of soliciting bids from potential construction managers for the work at Sanford Lab, and are on track to award the contract in January.

    Meanwhile, much progress is being made in developing the cryostats and particle detectors that will go into the caverns. At CERN, our colleagues are finishing construction of a building that will host two 6m x 6m x 6m cryostats. Then, this fall, the DUNE collaboration will begin construction of the two large DUNE prototype neutrino detectors (protoDUNEs) inside these cryostats. These prototypes will use and test the same full-scale detector components that will be used in the first two 17,700-ton liquid-argon detectors at Sanford Lab.

    So, clearly a lot of work ongoing – and getting DOE’s CD-3a approval to start the excavation work at Sanford Lab will enable us to ensure that the underground caverns are ready when needed by the DUNE experiment.

    Achieving this milestone is the result of a tremendous amount of work by the LBNF/DUNE project team, including our CERN partners; many staff and users here at Fermilab and our partners at Sanford Lab; the entire DOE team; and supporters at collaborating institutions around the world.

    LBNF and DUNE are proceeding well and on schedule, and I will continue to keep you updated on the project’s progress.

    See the full article here .

    Please help promote STEM in your local schools.

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    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 6:47 am on September 2, 2016 Permalink | Reply
    Tags: , Neutrinos, , ,   

    From U Rochester: “Why neutrinos ‘matter’ in the early universe” 

    U Rochester bloc

    University of Rochester

    August 30, 2016
    Monique Patenaude
    monique.patenaude@rochester.edu

    1
    T2K’s detector. (University of Tokyo photo / Kamioka Observatory, Institute for Cosmic Ray Research)

    Physicists love good symmetry—and that love is more than aesthetic appeal. One of the more important symmetries in all of science is the one between antimatter and matter.

    Energy in the early universe was transformed into equal parts of matter and antimatter. Barring anything else, those equal parts should have destroyed each other and left us with no matter with which to make stars and planets, and people and dogs.

    So physicists reason that something must have broken the matter-antimatter symmetry in the early universe, leaving us with a universe dominated by, well, stuff—one in which we (and dogs) can exist. The puzzle of how the matter-antimatter symmetry was broken is one of the great questions that particle physicists are trying to answer.

    University of Rochester graduate student, Konosuke (Ko) Iwamoto, updated the physics world on this question at the 38th biennial International Conference on High Energy Physics (ICHEP), in Chicago earlier this month.

    Iwamoto presented the highly anticipated findings from the Japan-based T2K neutrino experiment collaboration concerning the minute differences in the oscillations of subatomic particles called neutrinos and antineutrinos. (Almost every particle has an antimatter counterpart: a particle with the same mass but opposite charge.)

    T2K map
    T2K map

    The new results suggest that the matter-antimatter symmetry may have been broken by neutrinos. T2K’s experiments show that neutrinos and antineutrinos behave differently—the imbalance may have disrupted the matter/antimatter balance. Though the results are not conclusive—there is a 1-in-20 chance that their results are a fluke—but physicists are excited about the findings and further data gathering from T2K and other experiments is underway.

    “It is fabulous that Ko was chosen to present the findings of the T2K collaboration at ICHEP,” says Rochester professor of physics, Steven Manly. “ICHEP is the biggest international conference in particle physics and it was started in the 1950s by the then chair of Rochester’s physics department, Robert Marshak. Everyone still calls it the ‘Rochester conference.’”

    T2K is a large, international particle physics experiment operating in Japan. In this experiment, an intense beam of neutrinos is produced at the Japan Proton Accelerator Research Complex (J-PARC), which is located on the east coast of Japan, approximately 100 miles north of Tokyo. 185 miles away, the beam detector is located deep inside a mine in the mountains of western Japan. Physicists involved in the experiment measure how the neutrinos oscillate from one of three types, or “flavors,” to another during the transit across Japan.

    Japan Proton Accelerator Research Complex J-PARC
    Japan Proton Accelerator Research Complex J-PARC

    Professors Kevin McFarland and Manly lead the Rochester neutrino group on T2K. Members of the collaboration recently shared the 2016 Breakthrough Prize in Fundamental Physics “for the fundamental discovery and exploration of neutrino oscillations, revealing a new frontier beyond, and possibly far beyond, the standard model of particle physics.”

    See the full article here .

    Please help promote STEM in your local schools.

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    U Rochester Campus

    The University of Rochester is one of the country’s top-tier research universities. Our 158 buildings house more than 200 academic majors, more than 2,000 faculty and instructional staff, and some 10,500 students—approximately half of whom are women.

    Learning at the University of Rochester is also on a very personal scale. Rochester remains one of the smallest and most collegiate among top research universities, with smaller classes, a low 10:1 student to teacher ratio, and increased interactions with faculty.

     
  • richardmitnick 12:40 pm on August 30, 2016 Permalink | Reply
    Tags: , Neutrinos,   

    From IceCube: “Week 32 at the Pole” 

    icecube
    IceCube South Pole Neutrino Observatory

    26 Aug 2016
    Jean DeMeri

    What ever happened to the igloo from Weeks 30 and 31 at the Pole? Find out in Week 32 at the pole:

    1
    Hamish Wright, NSF

    The igloo—the prime attraction at the South Pole for the last few weeks—is no more. But before “disappearing,” its existence was memorialized in some final photos. Above, you can see it with the names of its builders carved into the side, and it appears to almost glow from the soft white light from within. The next image shows IceCube’s winterovers on the left along with the station’s water plant tech relaxing inside. Some folks took the opportunity to sleep (or attempt to sleep) in the igloo while it was still available—a thrill in and of itself but high winds in excess of 30 knots made it extra-exciting. A massive snow drift under the station entrance’s staircase attests to the ultrahigh winds last week. The last two images show the igloo before and during its ultimate demise. A shame to see it go, but that looks pretty cool. Until the next one!

    2
    Christian Krueger, IceCube/NSF

    3
    Christian Krueger, IceCube/NSF

    4
    Hamish Wright, NSF

    5
    Hamish Wright, NSF

    See the full article here .

    Please help promote STEM in your local schools.

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    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 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.

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    Symmetry is a joint Fermilab/SLAC publication.


     
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