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  • richardmitnick 3:39 pm on September 17, 2014 Permalink | Reply
    Tags: , , Particle Physics,   

    From Princeton: “Neutrino experiment that reaches for the sun has Princeton roots” 

    Princeton University
    Princeton University

    September 17, 2014
    Catherine Zandonella, Office of the Dean for Research

    The detection announced Aug. 28 of an elusive subatomic particle forged in the sun’s core was a crowning achievement in the 25-year international effort to design and build one of the most sensitive neutrino detectors in the world, a feat that directly involved Princeton University scientists and engineers. With ongoing improvements in its sensitivity, the Borexino neutrino detector located a mile beneath a mountaintop at Italy’s Gran Sasso National Laboratory has the potential to reveal more about how the sun and other stars produce energy.

    Gran Sasso
    LABORATORI NAZIONALI del GRAN SASSO

    Sometimes called “ghost particles,” neutrinos are extremely difficult to detect because they slip through ordinary matter without leaving a trace. The four-story high Borexino detector is one of a handful worldwide that are capable of detecting the weakest of the neutrinos, including the proton-proton solar neutrino that is emitted during the first of several fusion reactions that generate 99 percent of the sun’s energy. The discovery of the proton-proton neutrino was reported in the journal Nature.

    “The detection of this type of solar neutrino confirms an important piece of the theory about how the sun makes energy, and if you understand the sun then you understand stars in general,” said Professor of Physics Frank Calaprice, who has led Princeton’s part of the Borexino collaboration.

    image
    The Borexino collaboration, which announced the detection of an elusive solar neutrino in August, involved several scientific contributions from Princeton over its 25-year history. The detector consists of two massive transparent nylon balloons filled with a petroleum-based liquid called “scintillator,” which emits a flash of light when it detects a neutrino. These flashes are picked up by an array of sensors embedded in a stainless steel sphere that surrounds the balloons. (Image courtesy of the Borexino collaboration)

    Although proton-proton neutrinos have been detected indirectly, Borexino is the first to measure the particles directly as well as to count the rate at which neutrinos are produced. Knowing how many neutrinos are produced tells scientists how much solar energy is being generated at the core of the sun.

    It takes tens of thousands of years for the energy made in the sun’s center to migrate to its surface. Neutrinos, on the other hand, travel at near the speed of light, reaching Earth in about eight minutes. So neutrinos essentially reveal what the sun’s surface will be like thousands of years in the future. The Borexino result revealed that the sun’s energy as measured by proton-proton neutrinos agreed with the energy measured at the sun’s surface within about 10 percent, indicating that the sun’s energy output has remained stable over the last 100,000 years or so.

    In addition to providing a way of forecasting the sun’s energy production for the next 100,000 years, the detection of these fleeting solar particles offers a way to probe the composition of the sun’s core, Calaprice said: “In principle you can tell what is happening in the center of the sun by measuring these neutrinos.”

    The standard model of the sun suggests that it is a mixed ball of hydrogen and helium with trace amounts of oxygen, carbon, nitrogen and other elements. Studies of the sun’s seismic activity have challenged that finding, however, suggesting that the core of the sun contains greater amounts of carbon, nitrogen and oxygen, while the fringes contain more hydrogen and helium.

    A type of neutrino that has not been detected before but is predicted to exist — the carbon-nitrogen neutrino — could put the controversy to rest. These neutrinos form during the process that makes the other 1 percent of the sun’s energy. Although the carbon-nitrogen process contributes little to the total energy produced in slowly evolving stars such as our sun, it is common in massive, rapidly evolving stars in the universe.

    Borexino is close to having the sort of sensitivity needed to detect carbon-nitrogen neutrinos, Calaprice said. “If we measure carbon-nitrogen neutrinos, we may be able to learn something about the amount of carbon and other elements in the core of the sun,” he said. “This could help researchers explore whether the formation of the planets affected the composition of the outer zone of the sun.”

    Balloons in Jadwin Gym

    Princeton faculty members and students have been involved in the design and construction of Borexino since its inception in the early 1990s, Calaprice said. The project is funded by Italy’s National Institute for Nuclear Physics and the U.S. National Science Foundation, as well as by science agencies from Germany, Russia, Poland, Hungary and several other countries.

    The detector, which was switched on in 2007, consists of two giant, transparent nylon balloons, one nested inside the other, that are filled with a petroleum-based liquid called “scintillator,” which emits a flash of light when a neutrino is detected. That flash of light is picked up by roughly 2,000 sensors spaced evenly around the interior of a stainless steel sphere that surrounds the balloons.

    The idea for using balloons to contain the liquid came from Calaprice’s long-time colleague, Robert Parsells, an engineer at the Princeton Plasma Physics Laboratory. “It was one of those crazy ideas that sometimes work,” Calaprice said.

    pppl

    Engineers and students at Princeton designed and built the balloons under the guidance of Calaprice and Professor of Physics Cristiano Galbiati. The team included then-graduate students Laura Cadonati, now an associate professor of physics at the University of Massachusetts-Amherst, and Andrea Pocar, now an assistant professor at the University of Massachusetts-Amherst. With Princeton engineer Allan Nelson and others, the researchers assembled the balloons — which were 28-feet and 38-feet in diameter — by gluing together strips of nylon in a dust-free “cleanroom” in the physics building. They then inflated prototypes of the balloons for testing in Princeton’s Jadwin Gym before transporting them to Italy.

    While members of the collaboration from Italy and other nations worked on the network of sensors and the electronics to process the results, the Princeton team made sure that the entire detector was free from background contaminants that could obscure the results. “Within the collaboration, the Princeton group historically has tackled some of the most challenging aspects of the experiment,” said Pocar, who now works on Borexino data analysis at Amherst and served as the corresponding author on behalf of the collaboration for the finding reported in Nature.
    Balloon construction in clean room

    team
    In the early 2000s, Princeton graduate students and engineers built large transparent nylon balloons to contain the scintillator. The team glued strips of nylon together in a special cleanroom constructed in the physics building to be as free as possible of radioactivity and dust. From left to right: Andrea Pocar, then a graduate student and now an assistant professor at the University of Massachusetts-Amherst; the late John Bahcall, a physicist at the Institute of Advance Study, who was instrumental in studying solar neutrinos and advocating for the Borexino project; and Princeton technicians Charles Sule, Allan Nelson, Elizabeth Harding (in background) and Brian Kennedy. (Image courtesy of Frank Calaprice, Department of Physics)
    Leave no trace of radioactivity

    Solar neutrinos stream from the sun to Earth at a rate of 420 billion per second per square-inch but are invisible and harmless. Their signals are nearly impossible to distinguish from the signals coming from the decay of common radioactive elements such as radon. The extremely clean and radioactive-free environment achieved at the Borexino detector has enabled the elimination of false detections, yielding the sensitivity needed for the detection of the proton-proton neutrino, which was not part of the project’s original goals, Calaprice said: “No one really thought that we could succeed with this experiment — it was too hard to get the backgrounds down as low as were needed.”

    To reduce false readings from radioactive particles — which are common in rocks and water in Italy and New Jersey — Calaprice turned to Princeton’s Jay Benziger, professor of chemical and biological engineering, an expert in the industrial-scale refining of petroleum. “We realized we needed surfaces that dust cannot stick to, so we borrowed techniques from the pharmaceutical industry, and we used purification methods borrowed from the petroleum industry, all to get the background down,” Benziger said. The resulting purification system was built and tested at Princeton before being shipped to Gran Sasso.

    In the past three years, a team of undergraduates successfully improved the purification process. Puzzled by the difficulty of removing a certain radioactive element called polonium-210, Brooke Russell, a Class of 2011 physics student who stayed on as a staff researcher, discovered a publication showing that the polonium can be converted by bacteria to another compound that allows it to resist being removed by the techniques the group was using. The team, which included William Taylor, Class of 2014, and Christian Aurup, a summer research associate and undergraduate at the University of Delaware, made adjustments to the procedure that dramatically reduced the level of the contamination. The techniques developed at Princeton to prevent false detections at Borexino have been employed in the DarkSide dark matter detector also located at Gran Sasso, as well as other neutrino and dark matter detectors around the world.

    “The thesis experience and also the two years after graduation were really pivotal for me,” Russell said. “Before doing my thesis, I had not been exposed to experimental physics. I enjoyed it so thoroughly that I decided to pursue it as a career,” said Russell, who is now in her second year of graduate studies at Yale University.

    With this latest purification step, Calaprice said, he hopes that Borexino can detect the last known solar neutrino, the carbon-nitrogen neutrino. The detector also will begin searching for the so-called “sterile neutrino” that some physicists think exists. If it is found, this type of neutrino could explain discrepancies in the so-called Standard Model of particle physics.

    sm
    The Standard Model of elementary particles, with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    The international team that reported the proton-proton neutrino in the August 28 issue of Nature included the following Princeton researchers: Borexino general engineers Augusto Goretti and Andrea Ianni; Alvaro Chavarria, who earned his doctorate in physics in 2012; Pablo Mosteiro, who earned his doctorate in physics in 2014; Richard Saldanha, who earned his doctorate in physics in 2012; R. Bruce Vogelaar, a former assistant professor now at Virginia Polytechnic Institute and State University; and Alex Wright, former postdoctoral researcher and now assistant professor at Queen’s University.

    The article, “Neutrinos from the primary proton–proton fusion process in the Sun,” was published Aug. 28 in Nature.

    See the full article here.

    About Princeton: Overview

    Princeton University is a vibrant community of scholarship and learning that stands in the nation’s service and in the service of all nations. Chartered in 1746, Princeton is the fourth-oldest college in the United States. Princeton is an independent, coeducational, nondenominational institution that provides undergraduate and graduate instruction in the humanities, social sciences, natural sciences and engineering.

    As a world-renowned research university, Princeton seeks to achieve the highest levels of distinction in the discovery and transmission of knowledge and understanding. At the same time, Princeton is distinctive among research universities in its commitment to undergraduate teaching.

    Today, more than 1,100 faculty members instruct approximately 5,200 undergraduate students and 2,600 graduate students. The University’s generous financial aid program ensures that talented students from all economic backgrounds can afford a Princeton education.

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  • richardmitnick 12:48 pm on September 16, 2014 Permalink | Reply
    Tags: , Particle Physics, , ,   

    From phys.org: “Neutrino trident production may offer powerful probe of new physics” 

    physdotorg
    phys.org

    September 15, 2014
    Lisa Zyga

    The standard model (SM) of particle physics has four types of force carrier particles: photons, W and Z bosons, and gluons. But recently there has been renewed interest in the question of whether there might exist a new force, which, if confirmed, would result in an extension of the SM. Theoretically, the new force would be carried by a new gauge boson called Z’ or the “dark photon” because this “dark force” would be difficult to detect, as it would affect only neutrinos and unstable leptons.

    sm
    The Standard Model of elementary particles, with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    “Much of the complexity and beauty of our physical world depends on only four forces,” Wolfgang Altmannshofer, a researcher at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, told Phys.org. “It stands to reason that any additional new force discovered will bring with it interesting and unexpected phenomena, although it might take some time to fully appreciate and understand its implications.”

    Now in a new study published in Physical Review Letters, Altmannshofer and his coauthors from the Perimeter Institute have shown that the parameter space where a new dark force would exist is significantly restricted by a rare process called neutrino trident production, which has only been experimentally observed twice.

    graph
    Parameter space for the Z’ gauge boson. The light gray area is excluded at 95% C.L. by the CCFR measurement of the neutrino trident cross section. The dark gray region with the dotted contour is excluded by measurements of the SM Z boson decay to four leptons at the LHC. The purple region is the area favored by the muon g-2 discrepancy that has not yet been ruled out, but future high-energy neutrino experiments are expected to be highly sensitive to this low-mass region. Credit: Altmannshofer, et al. ©2014 American Physical Society

    In neutrino trident production, a pair of muons is produced from the scattering of a muon neutrino off a heavy atomic nucleus. If the new Z’ boson exists, it would increase the rate of neutrino trident production by inducing additional particle interactions that would constructively interfere with the expected SM contribution.

    The new force could also solve a long-standing discrepancy in the [Fermilab] muon g-2 experiment compared to the SM prediction. By coupling to muons, the new force might solve this problem.

    However, the two existing experimental results of neutrino trident production (performed by the CHARM-II collaboration and the CCFR collaboration) are both in good agreement with SM predictions, which places strong constraints on any possible contributions from a new force.

    In the new paper, the physicists have analyzed the two experimental results and extended the support for ruling out a dark force, at least over a large portion of the parameter space relevant to solving the muon g-2 discrepancy (when the mass of the Z’ boson is greater than about 400 MeV). The results not only constrain the dark force, but more generally any new force that couples to both muons and muon neutrinos.

    “We showed that neutrino trident production is the most sensitive probe of a certain type of new force,” Altmannshofer said. “Particle physics is driven by the desire to discover new building blocks of nature, and ultimately the principles that organize these building blocks. Our findings establish a new direction where new forces can be searched for, and highlight the planned neutrino facility at Fermilab (the Long-Baseline Neutrino Experiment [LBNE]) as a potentially powerful experiment where such forces can be searched for in the future.”

    Overall, the current results suggest that LBNE would have very favorable prospects for searching for the Z’ boson in the relevant, though restricted, regions of parameter space.

    See the full article here.

    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

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  • richardmitnick 10:50 am on September 16, 2014 Permalink | Reply
    Tags: , , , , New Scientist, , Particle Physics   

    From New Scientist: “Curtain closing on Higgs boson photon soap opera” 

    NewScientist

    New Scientist

    15 September 2014
    Michael Slezak

    It was the daytime soap opera of particle physics. But the final episode of the first season ends in an anticlimax. The Higgs boson‘s decay into pairs of photons – the strongest yet most confusing clue to the particle’s existence – is looking utterly normal after all.

    Experiments don’t detect the Higgs boson directly – instead, its existence is inferred by looking at the particles left behind when it decays. One way it made itself known at CERN’s Large Hadron Collider near Geneva, Switzerland, two years ago was by decaying into pairs of photons. Right at the start, there were so many photons that physicists considered it a “deviant decay” – and a possible window into new laws of physics, which could help explain the mysteries of dark energy and the like.

    CERN LHC Grand Tunnel
    CERN LHC Map
    CERN LHC particles
    LHC at CERN

    Even as other kinks in the data got ironed out, the excess of photons remained. At the time, physicists speculated that it could be due to a mysterious second Higgs boson being created, or maybe the supersymmetric partner of the top quark.

    Supersymmetry standard model
    Standard Model showing Supersymmetric Particles

    Identity crisis

    If unheard of particles and physical laws weren’t dramatic enough, six months later, the decay into photons was giving the Higgs an identity crisis. When physicists measured the Higgs mass by observing it decaying into another type of particle, called a Z boson, it appeared lighter than when doing a similar calculation using the decay into photons. “The results are barely consistent,” Albert de Roeck, one of the key Higgs hunters at CERN’s CMS experiment, said at the time.

    But over the past year, physicists at CERN have found that the Higgs boson is acting exactly as the incomplete standard model of particle physics predicts, leaving us with no clues about how to extend it.

    Now, in an anticlimactic summary on the two photon decay, both big experiments at the LHC have posted results showing the photons are, after all the fuss, also doing exactly what the standard model predicts.

    Powering up

    “This is probably the final word,” wrote CERN physicist Adam Falkowski on his blog.

    Ever the optimist, de Roeck thinks there’s still room in the data for the two photon decay channel to be caught misbehaving. Our present outlook is due to our relatively fuzzy view of the behaviour so far, he says. When the LHC is switched back on next year after an upgrade, it will be smashing protons together with double the previous energy.

    With that kind of power, the measurements will be more exact, and any small deviations from standard model predictions could emerge. “It is most likely the last word for run one of the LHC, but definitely not the last word,” de Roeck says. “I still believe ultimately we will find significant deviations or something unexpected in the Higgs sector. Then all hell will break loose.”

    See the full article here.

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  • richardmitnick 4:04 pm on September 7, 2014 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From Don Lincoln for JHU Press: “Damage to the Large Hadron Collider” 

    jhu

    FNAL Don Lincoln
    FNAL’s Dr. Don Lincoln

    September 5, 2014

    A spark. That’s all it was . . . just a little spark . . . in a vacuum, no less. It sounds so harmless. What could it hurt? Let’s see how the story unfolds.

    Well, time, which is measured in microseconds at this point, moved on. The spark jumped from copper conductor to copper conductor, causing copper atoms to be knocked off into the vacuum. As the amount of copper vapor grew, the vacuum became less of an insulator and more conductive, letting more electricity flow. That’s when things began to get interesting. Like opening a faucet completely, the trickle of the initial spark grew until it became a torrent of electricity: ten thousand amperes, enough to simultaneously start thirty or so cars in the dead of winter. The onslaught of electricity was enough to melt a chunk of copper the size an adult fist. This would be bad, but, if you will excuse the pun, things were just beginning to heat up.

    The tipping point from annoying incident to serious disaster occurred when the heat from the electrical arc punctured the volume filled with the liquid helium used to cool the Large Hadron Collider magnets to more than 450° Farenheit below zero. Luckily, helium is an inert gas, so an explosion in the usual sense of the word was impossible. However, the helium was in liquid form, and when it encountered more ordinary temperatures, it boiled and turned into gas. When any liquid turns to gas at atmospheric temperature, it expands in volume to 700 times its ordinary size. And the LHC magnets contain an awful lot of helium . . . as in 96 tons of helium. (Although, in the end, only six tons were released.)

    As the helium vented from the storage volume, it jetted out with tremendous force. And by “tremendous force,” I mean enough force to move a 50-foot-long magnet weighing 35 tons and anchored to the concrete floor about two feet. As the helium gas expanded in the LHC tunnel, it pushed air out of the way. The boundary between an environment containing ordinary air and one containing only helium moved up the tunnel at incredible speed. It was possible for a human to outrun the helium monster, but only if the person could run a four-minute mile. Run any slower, and you would be overtaken by helium. Soon, you would fall down and die, suffocated by lack of oxygen.

    Luckily, there was nobody near the punctured helium volume to be in danger. Actually, luck had nothing to do with it. The CERN (European Organization for Nuclear Research) safety professionals were aware of the danger of a catastrophic failure. Although such an incident was extremely unlikely, people are allowed in the Large Hadron Collider tunnel only rarely. If they are allowed inside, they must have special training and carry oxygen tanks and protective clothing. In this case, however, the nearest CERN personnel were miles away from the incident, and even the civilians who lived above the LHC were separated by at least 300 feet of solid rock. No people were ever in danger.

    I was in the United States on the day in September 2008 when the LHC broke. My colleagues and I were getting reports second-hand, and I remember well the group sitting around a table, looking shell-shocked, and asking each other, “How bad can it be?”

    So now, in the fullness of time, we can answer that question. How bad was it? Pretty bad. Repairing the LHC cost tens of millions of dollars and took about a year. In the end, fifty-three magnets, each fifty feet long and weighing thirty-five tons, needed to be removed, repaired, cleaned, and replaced. While the true damage was relatively localized, among the collateral damage was a breeching of the LHC’s beam pipe, into which soot and debris spread for a mile or so. The technicians were busy.

    It is now six years later, and perhaps it is time for a broader viewpoint. Yes, the damage was grave, and yes, it took a year to repair. However, the repair costs were about two percent the cost of the entire LHC, and the delay was only about five percent of the schedule. Granted, if you were a graduate student who was hoping to graduate on the first year’s data, the incident was an awful delay. However, now, in 2014, what was the real consequence? Well, we now have an accelerator that is better instrumented against similar incidents. The damage of 2008 won’t occur again. We have studied billions of particle collisions and begun to explore the behavior of matter under conditions never before possible. We have discovered the Higgs boson and facilitated a Nobel Prize in physics. There have been some considerable successes, and the debacle of 2008 is now fading into distant memory.

    It’s all a matter of perspective. And, let us not forget, the data of 2015 beckons alluringly. Soon the universe will give up some more of her mysteries and scientists will do what they have for millennia: they will take up their pens and begin writing a new page in the book of knowledge, a book whose first pages were penned over two thousand years ago.

    Perspective.

    Don Lincoln is a senior scientist at Fermi National Accelerator Laboratory and an adjunct professor of physics at the University of Notre Dame. He is the author of

    The Large Hadron Collider: The Extraordinary Story of the Higgs Boson and Other Stuff That Will Blow Your Mind
    book

    , Alien Universe: Extraterrestrials in Our Minds and in the Cosmos
    book3

    and The Quantum Frontier: The Large Hadron Collider,
    book2

    all published by Johns Hopkins.

    See the full article here.

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  • richardmitnick 10:41 am on September 4, 2014 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From FNAL- “Frontier Science Result: CDF The final word on Z’s and jets from CDF” 


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

    Thursday, Sept. 4, 2014
    edited by Andy Beretvas

    charts
    Inclusive jet pT differential cross sections for Z + one or more jet events. The measured differential cross section (black dots) is compared to the LOOPSIM + MCFM prediction (open circle). On the right many other theoretical predictions are shown.

    Our understanding of the strong force, called QCD (quantum chromodynamics) is very advanced. This theory describes the interactions between some of nature’s fundamental building blocks, quarks and gluons.

    quark
    A proton, composed of two up quarks and one down quark. (The color assignment of individual quarks is not important, only that all three colors be present.)

    inter
    In Feynman diagrams, emitted gluons are represented as helices. This diagram depicts the annihilation of an electron and positron.

    The highly energetic quarks and gluons released in the Tevatron proton-antiproton collisions produce collimated jets of particles, which can be detected by the experiments. These jets were produced in association with particles known as Z bosons.

    Fermilab Tevatron
    Tevatron at Fermilab

    You may know the Z as one of the carriers of the electroweak force, but here our focus is on their production in association with jets. The behavior of both the Z and the jets is predicted by the strong force.

    Scientists at the Tevatron experiments have made many measurements of the Z particle, which decays into a pair of leptons (electrons or muons) and jets. Our results correspond to the full Tevatron Run II data set (9.6 inverse femtobarns). In this experiment we are concerned with comparing measured probabilities with theoretical predictions. This is complicated because we must understand how well the detector records the decay particles’ tracks and energies for the process of Z boson and jet production.

    The inclusive Z-plus-jets decay probabilities are measured for one, two, three and four jets. The results shown are from combining the decay modes in which the Z decays into an electron pair and in which it decays into a muon pair. This is the first CDF measurement of probabilities for decays into a Z particle and three or more jets.

    The samples are very clean, and for the cases in which they include one or more jets, they contain only about 1.5 percent background. In the upper figure you can see results for the transverse momentum of the leading jet’s differential reaction probability for Z plus one or more jet events.

    This result is of great interest to many theoretical physicists as can be seen by the large number of predictions. The agreements are good as can be expected, as theorists have looked at earlier results from CDF and DZero. The most accurate predictions are those of a simulation program called LOOPSIM + MCFM. This is an important Tevatron legacy measurement.

    Fermilab CDF
    CDF at Fermilab

    Fermilab DZero
    DZero at Fermilab

    The results show beautiful agreement between theory and experiment and are important for understanding the association of Z and jets in searches for non-Standard Model physics.

    See the full article here.

    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.

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  • richardmitnick 11:49 am on September 3, 2014 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From Fermilab: “From the Technical Division – Leading the way in superconducting magnets and accelerators” 


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

    Wednesday, Sept. 3, 2014

    hm
    Hasan Padamsee, head of the Technical Division, wrote this column.

    I feel very fortunate to head the Technical Division in this era of exciting accelerator technology developments. Our division holds the keys to enabling technologies for frontier accelerators, both in magnet development and accelerator cavities.

    Our niobium titanium magnet program will guide intense muon beams for precision experiments to determine whether muons, which belong to the lepton family, can spontaneously change into other leptons — specifically electrons — just as neutrinos can change into other neutrinos [electron, muon, and tau]. The magnets for the Mu2e experiment will be wound with 45 miles of superconducting cable.

    Our Nb3Sn magnet advances will enable planned upgrades to LHC luminosity guided by the LARP program, led by Giorgio Apollinari. Our Nb3Sn and high-temperature superconductor high-field magnet program, led by Alexander Zlobin, could enable a roughly 100-TeV proton-proton collider, a most powerful tool for future high-energy physics.

    As an expert in superconducting radio-frequency acceleration technology, or SRF, I was thrilled to join Fermilab in June because I saw how the division mastered our new technology to build up the infrastructure and expertise through the International Linear Collider R&D program, which ran under the leadership of Bob Kephart and previous Technical Division Head Dave Harding. To our delight, the SRF Department, led by Slava Yakovlev, had prepared some of the best niobium cavities and assembled them into the world’s highest-gradient ILC cryomodule, with a gradient of 31.5 megavolts per meter. Thus the division played a huge role in getting SRF technology ready for the ILC, if and when it will be built.

    A major consequence of the SRF successes is the decision to upgrade LCLS, the world-class light source at SLAC, using SRF technology. While the ILC must be a pulsed accelerator with a one percent duty factor, meaning that the RF power remains on for only one percent of the time, the LCLS-II light source must run continuously to keep its users happy. Continuous operation is now made economically feasible thanks to spectacular discoveries from the Technical Division.

    Anna Grassellino and Alexander Romanenko discovered new phenomena in SRF that will raise the Q values — measures of how efficiently a cavity stores energy — of ILC-type accelerating cavities from 10 billion to nearly 30 billion. To appreciate the significance of such high Qs, imagine that Galileo’s pendulum oscillator — in the year 1600 — had a Q of 30 billion. It would still be oscillating today and would continue to oscillate to the year 2800! Such high Qs arise thanks to minuscule RF losses, which make it affordable to run superconducting cavities in LCLS-II continuously. The division is gearing up to provide 17 ILC-type cryomodules with 136 cavities, as well as two cryomodules with higher-frequency cavities.

    To reap the benefits at home, SRF is also the foundation of a brand new accelerator, called PIP-II, to be constructed at Fermilab to provide the world’s best neutrino beams. PIP-II will be built in collaboration with other labs to provide a 1-megawatt proton beam accelerated by an 800-MeV superconducting linac. The linac will contain almost 20 cryomodules with more than 110 SRF cavities. The prototype cavities have been constructed and tested successfully, and the first prototype cryomodules will be assembled next year.

    Both superconducting magnets and superconducting RF have brilliant futures at Fermilab. I am proud to lead these exciting developments to keep Fermilab at the frontier of high-energy physics.

    See the full article here.

    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.

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  • richardmitnick 12:18 pm on August 30, 2014 Permalink | Reply
    Tags: , , , , , , Particle Physics   

    From Don Lincoln at Fermilab: “Particle Detectors Subatomic Bomb Squad ” a Great Video 


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

    The manner in which particle physicists investigate collisions in particle accelerators is a puzzling process. Using vaguely-defined “detectors,” scientists are able to somehow reconstruct the collisions and convert that information into physics measurements. In this video, Fermilab’s Dr. Don Lincoln sheds light on this mysterious technique. In a surprising analogy, he draws a parallel between experimental particle physics and bomb squad investigators and uses an explosive example to illustrate his points. Be sure to watch this video… it’s totally the bomb.

    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.

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  • richardmitnick 9:49 am on August 28, 2014 Permalink | Reply
    Tags: , , , , Particle Physics   

    From Fermilab: “Director’s Corner – Restructuring the FRA Board” 


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

    nl
    Fermilab Director
    Nigel Lockyer

    Fermi Research Alliance LLC, the operator of Fermilab for the U.S. Department of Energy and a partnership between the University of Chicago and Universities Research Association, is reorganizing its board of directors this fall to best support the laboratory as it shapes its future as a world-leading scientific institution, working in close partnership with the scientific community to ensure a bright future for U.S. particle physics.

    The FRA Board provides strategic guidance, oversight, direction and advice to Fermilab management. The reorganized 15-member board will strongly emphasize support and advice in matters of project management, governance, industrial expertise, government relations and international collaboration.

    This expertise on our board will be crucial as we continue the work already begun to restructure and realign our lab to match the demands of the P5 plan. The plan calls on Fermilab to transform into a laboratory capable of hosting a world-leading international accelerator-based neutrino program while playing key roles in Large Hadron Collider research, muon physics, and the quest to understand dark matter and energy.

    The P5 plan highlights one major challenge our laboratory will face over the next decade: carrying out the largest suite of construction projects within the DOE Office of Science. Another is developing an Illinois Accelerator Research Center program that turns Fermilab into a hub for industrial development of the next generation of particle accelerators, products and applications.

    The goal of a reorganized board will be to support the lab management team as we seek to meet these challenges and to improve our overall operations performance. The board will also continue to assess our scientific strategy, in close consultation with the Physics Advisory Committee and as guided by national advisory groups.

    The reorganization was determined by the two members of FRA, the University of Chicago and Universities Research Association Inc. It will be overseen by an interim board that will be convened on Oct. 1. The interim board will include Robert J. Zimmer, chairman of the board and president of the University of Chicago; vice chairman of the board and Michigan State University President Lou Anna K. Simon; Marta Cehelsky, executive director of Universities Research Association; and Donald Levy, vice president for research and national laboratories at the University of Chicago. The full board reorganization will be completed in 2015.

    See the full article here.

    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.

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  • richardmitnick 9:34 am on August 28, 2014 Permalink | Reply
    Tags: , , , , Particle Physics   

    From Fermilab- “Frontier Science Result: DZero Which way did it go?” 


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

    Thursday, Aug. 28, 2014
    Leo Bellantoni

    In the DZero detector., the direction in which a particle travels — the direction of its momentum — is often easier to measure precisely than its energy or, equivalently, its amount of momentum. This is the key idea behind a recent result.

    Fermilab DZero
    DZero

    Put a flat piece of paper on your desktop. This is what particle physicists call the transverse plane. Now take a pencil and try to balance it on its point on the paper. You don’t have to succeed — just get the idea of something going perpendicularly into the paper. This depicts the proton going into the collision. The antiproton is traveling in the opposite direction, also perpendicular to the paper (excuse me: also perpendicular to the transverse plane). If the two are aligned and strike each other, then there is a collision point in the transverse plane. Pick the pencil up; there might be a little mark left from the pencil tip to show you where the collision happened.

    pro
    The quark structure of the proton. (The color assignment of individual quarks is not important, only that all three colors are present.)

    anti
    The quark structure of the antiproton.

    Now let us draw some arrows coming out from that little mark. These are the directions of the particles coming out of the collision. By drawing them on the paper, you draw only two dimensions of the motion — a particle might come out with a motion that is partly upwards and to the left, but on the paper you can only draw it to the left. This is what particle physicists call projecting onto the transverse plane.

    plane

    In the above figure you see a pair of possibilities for the projection onto the transverse plane of two particles from a collision. These two particles are the decay products of a very heavy particle created in the collision. The two particles on the left came from some heavy particle that was clearly headed south according to the compass. The two particles on the right came from a heavy particle that was clearly going nowhere.

    The method of the recent DZero result is a bit more complicated than this, but you have enough to get the basic idea. When a proton and an antiproton collide and produce a Z boson, the Z boson might decay into a pair of muons. The direction of the muons tells us how the Z was moving in the transverse plane. What scientists actually do is take the angle that you see in the figure, which is called the acoplanarity, and apply a certain correction to it to obtain an angle that theorists can predict and experimentalists can measure. More to the point, this angle, called Φ* and invented in part by DZero collaborators, is experimentally a more precise measure of the motion of the Z (as projected onto the transverse plane) than that obtained by measuring just the momentum of the muons in the transverse plane directly.

    The theoretical prediction relies on being able to calculate the effects of the strong nuclear force accurately, and this is a notoriously difficult thing to do. So in this case, comparing the data to the prediction is more a test of our ability to apply the theory than a test of the theory itself.

    DZero finds that the data and the theoretical predictions are in good but not perfect agreement. At Φ* near 30 degrees, the DZero measurement is higher than the prediction, but the prediction is not very definite. Now it is the theorists’ turn to try to improve our ability to apply the theory.

    See the full article here.

    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.

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  • richardmitnick 7:49 pm on August 27, 2014 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From isgtw: “Preserving three decades of Tevatron data” This is important. 


    international science grid this week

    August 27, 2014
    Hanah Chang

    No longer active, the Tevatron was host to the Collider Detector at Fermilab (CDF) and DZero experiments, and is recognized for the discovery of the top quark and for providing evidence for the existence of the Higgs boson, which was confirmed at CERN in 2012. Several years later, there is a continued effort to preserve the data resulting from the Tevatron’s three-decade legacy.

    Fermilab CDF
    CDF at Fermilab

    Fermilab DZero
    DZero at Fermilab

    Tevatron
    Tevatron

    The Run II Data Preservation system is expected to be sustainable through the year 2020. The project is moving progressively, having successfully tested both the CDF and DZero pilot systems. Tape migration is continuing on schedule, and both the hardware and software infrastructures have been running since February 2012. One of the biggest misconceptions about what data preservation entails, is that only the data is preserved on tape — when, in fact, the more difficult task is preserving the software and an environment on which it can run.

    Willis Sakumoto, a senior scientist at Fermi National Accelerator Laboratory (Fermilab), confirms ongoing efforts to fully integrate CDF data into the Fermilab Intensity Frontier Structure and provide Run II documentation within the scope of the project. These efforts include running compatibility validation tests for the transition from Root4 to Root5, as well as the integration of the Cern Virtual Machine File System (CernVM-FS). “The project is well on its way to accomplishing its goal of handing off CDF analysis and documentation infrastructure to Fermilab Scientific Computing Division (FSCD) operations.”

    Michelle Brochmann, a student working on the DZero data preservation project, is also optimistic about the progress made thus far. “CernVM-FS facilitates cooperation among scientists by enabling them to access a consistent computational analysis environment.” It has some nice features: the software appears local despite being stored remotely, and files are accessed quickly because CernVM-FS uses optimized, existing http infrastructure and only fetches files from the remote server as they are needed. “Fermilab has committed to help maintain the CernVM-FS for the next decade or so,” adds Brochmann.

    Challenges the Run II Data Preservation team must overcome include lack of new resources and manpower. Fortunately, scientists like Kenneth Herner and Bo Jayatilaka — who have worked on the DZero and CDF experiments respectively — recognize the value of the labor they are putting forth and the overall significance it could have for a scientist who may need to revisit a measurement or make new theoretical calculations. “This data has the potential to make new discoveries,” says Jayatilaka.

    The growing spread of digital science means not only data but also software preservation is of critical importance to the long-term value of research outcomes. As the magnitude of the experiments — both in cost and in labor — increase, the need for a common forum of usable data is amplified. In response, projects such as the Data and Software Preservation for Open Science (DASPOS) and the Study Group for Data Preservation in High Energy Physics (DPHEP) are working to expand and improve data preservation technology.

    Sakumoto is planning to integrate the use of cloud-based technology as a possible analysis solution. Regardless of the methodology chosen, the need for sustainable data preservation will continue to increase as science advances, experiments become less replicable, and data sets become more unique.

    See the full article here.

    iSGTW is an international weekly online publication that covers distributed computing and the research it enables.

    “We report on all aspects of distributed computing technology, such as grids and clouds. We also regularly feature articles on distributed computing-enabled research in a large variety of disciplines, including physics, biology, sociology, earth sciences, archaeology, medicine, disaster management, crime, and art. (Note that we do not cover stories that are purely about commercial technology.)

    In its current incarnation, iSGTW is also an online destination where you can host a profile and blog, and find and disseminate announcements and information about events, deadlines, and jobs. In the near future it will also be a place where you can network with colleagues.

    You can read iSGTW via our homepage, RSS, or email. For the complete iSGTW experience, sign up for an account or log in with OpenID and manage your email subscription from your account preferences. If you do not wish to access the website’s features, you can just subscribe to the weekly email.”

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