143 research outputs found

    Criticality in a Vlasov-Poisson system - a fermionic universality class

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    A model Vlasov--Poisson system is simulated close the point of marginal stability, thus assuming only the wave-particle resonant interactions are responsible for saturation, and shown to obey the power--law scaling of a second-order phase transition. The set of critical exponents analogous to those of the Ising universality class is calculated and shown to obey the Widom and Rushbrooke scaling and Josephson's hyperscaling relations at the formal dimensionality d=5d=5 below the critical point at nonzero order parameter. However, the two-point correlation function does not correspond to the propagator of Euclidean quantum field theory, which is the Gaussian model for the Ising universality class. Instead it corresponds to the propagator for the fermionic {\it vector} field and to the {\it upper critical dimensionality} dc=2d_c=2. This suggests criticality of collisionless Vlasov-Poisson systems as representative of the {\it universality class} of critical phenomena of {\it a fermionic} quantum field description.Comment: 10 pages, 6 figures, Submitted to Phys. Rev.

    Imprints, [Vol. 5]

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    This 1989 edition includes winners of the T. E. Ferguson writing Contest, two honorable mentions, and a number of other entries that we felt deserved to be published. I would like to give special thanks to all the judges of the Ferguson Writing Contest who helped make this publication possible, and especially to Dr. Patricia Russell, who one again proved to be an invaluable asset. Her dedication and love for the organization and all it stands for has made this one of the most successful years ever.https://scholarworks.sfasu.edu/imprints/1000/thumbnail.jp

    Imprints, Vol. 5

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    This 1989 edition includes winners of the T. E. Ferguson writing Contest, two honorable mentions, and a number of other entries that we felt deserved to be published. I would like to give special thanks to all the judges of the Ferguson Writing Contest who helped make this publication possible, and especially to Dr. Patricia Russell, who one again proved to be an invaluable asset. Her dedication and love for the organization and all it stands for has made this one of the most successful years ever

    The SCUBA-2 Cosmology Legacy Survey:850um maps, catalogues and number counts

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    We present a catalogue of nearly 3,000 submillimetre sources detected at 850um over ~5 square degrees surveyed as part of the James Clerk Maxwell Telescope (JCMT) SCUBA-2 Cosmology Legacy Survey (S2CLS). This is the largest survey of its kind at 850um, probing a meaningful cosmic volume at the peak of star formation activity and increasing the sample size of submillimetre galaxies selected at 850um by an order of magnitude. We describe the wide 850um survey component of S2CLS, which covers the key extragalactic survey fields: UKIDSS-UDS, COSMOS, Akari-NEP, Extended Groth Strip, Lockman Hole North, SSA22 and GOODS-North. The average 1-sigma depth of S2CLS is 1.2 mJy/beam, approaching the SCUBA-2 850um confusion limit, which we determine to be ~0.8 mJy/beam. We measure the single dish 850um number counts to unprecedented accuracy, reducing the Poisson errors on the differential counts to approximately 4% at S_850~3mJy. With several independent fields, we investigate field-to-field variance, finding that the number counts on 0.5-1 degree scales are generally within 50% of the S2CLS mean for S_850>3mJy, with scatter consistent with the Poisson and estimated cosmic variance uncertainties, although there is a marginal (2-sigma) density enhancement in the GOODS-North field. The observed number counts are in reasonable agreement with recent phenomenological and semi-analytic models. Finally, the large solid angle of S2CLS allows us to measure the bright-end counts: at S_850>10mJy there are approximately ten sources per square degree, and we detect the distinctive up-turn in the number counts indicative of the detection of local sources of 850um emission and strongly lensed high-redshift galaxies. Here we describe the data collection and reduction procedures and present calibrated maps and a catalogue of sources; these are made publicly available

    Early Detection and Monitoring of Cancer with the Anti-Malignin Antibody Test "

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    ABSTRACT: The serum anti-malignin antibody (AMA) test determines the antibody to malignin. a IO,OOO-Da peptide present in patients with a wide variety of cancers.l~ A total of 3315 double-blind tests demonstrated that AMA is a general transformation antibody, elevated in active no.nterminal cancer, regardless of the site or tissue type, with sensitivity and specificity of95% on the flTst determination and >99% on repeat determinations. - 9 Data have not however been published yet that indicate whether, in daily clinical practice, the AMA test provides accurate prospective and predictive information. Fony-two physicians from II states, who ordered the AMA test, performed blind, report here on their results on 208 determinations in the first consecutive 181 patients and controls. Used in monitoring treatment in 56 patients, the test predicted or agreed 94.1 % overall with the clinical status. Used in early detection in 125 patients and controls, of which 118 now have confirmed diagnoses. AMA was elevated in 21, all of whom were proven to have cancer; AMA was normal in 97, none of whom had cancer. Transient elevated AMA occurred in 3%, followed by normal values. Seven patients with still uncertain diagnosis who have had elevated AMA on repeated tests for I year or longer include six who are symptomatic, and three whose families have a high frequency of cancer. The conditions of these 7 may include undetected cancer because of the 118 with now certain diagnosis the AMA test predicted all correctly. From our experience, the AMA test should be used together with other routine procedures whenever signs and symptoms suggest cancer to facilitate early detection

    Design, construction and operation of the ProtoDUNE-SP Liquid Argon TPC

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    The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, USA. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7×6×7.27\times 6\times 7.2~m3^3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP's successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∌99% of the euchromatic genome and is accurate to an error rate of ∌1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Institutional Labor Economics, the New Personnel Economics, and Internal Labor Markets: A Reconsideration

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    The author illustrates the utility of institutional labor economics and makes a case for a reconsideration of it. Two recent developments motivate this effort: the rise of New Personnel Economics (NPE) as a significant subfield of labor economics and the substantial shifts in work organization that have taken place since the 1990s. Understanding how and why firms have reorganized work opens the door for a renewed interest in institutional approaches. The author explains that the rules of institutional labor markets (ILMs) emerge from the competition between organizational interest groups—unions, personnel professionals, and the government—and competing views of firms’ objectives—resulting in the rise of ILMs, the slow diffusion of High Performance Work Systems, strategies used to obtain a high level of commitment from workers, the use of contingent employees, and the spread of new promotion rules in response to equal employment opportunity pressures. As such, the role of power and influence in establishing work rules is of central concern, though more conventional NPE considerations also remain important

    Searching for solar KDAR with DUNE

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    Abstract: The observation of 236 MeV muon neutrinos from kaon-decay-at-rest (KDAR) originating in the core of the Sun would provide a unique signature of dark matter annihilation. Since excellent angle and energy reconstruction are necessary to detect this monoenergetic, directional neutrino flux, DUNE with its vast volume and reconstruction capabilities, is a promising candidate for a KDAR neutrino search. In this work, we evaluate the proposed KDAR neutrino search strategies by realistically modeling both neutrino-nucleus interactions and the response of DUNE. We find that, although reconstruction of the neutrino energy and direction is difficult with current techniques in the relevant energy range, the superb energy resolution, angular resolution, and particle identification offered by DUNE can still permit great signal/background discrimination. Moreover, there are non-standard scenarios in which searches at DUNE for KDAR in the Sun can probe dark matter interactions
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