390 research outputs found

    Simple Classification of Light Baryons

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    We introduce a classification number nn which describes the baryon mass information in a fuzzy manner. According to nn and JpJ^p of baryons, we put all known light baryons in a simple table in which some baryons with same (nn, JpJ^p) are classified as members of known octets or decuplets. Meanwhile, we predict two new possible octets.Comment: 5 latex pages, 5 tables, no figur

    Very Long Baseline Neutrino Oscillation Experiment for Precise Measurements of Mixing Parameters and CP Violating Effects

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    We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline (BVLB) neutrino oscillation experiment consisting of a conventional horn produced low energy wide band beam and a detector of 500 kT fiducial mass with modest requirements on event recognition and resolution. Such an experiment is intended primarily to determine CP violating effects in the neutrino sector for 3-generation mixing. We analyze the sensitivity of such an experiment. We conclude that this experiment will allow determination of the CP phase δCP\delta_{CP} and the currently unknown mixing parameter θ13\theta_{13}, if sin22θ130.01\sin ^2 2 \theta_{13} \geq 0.01, a value 15\sim 15 times lower than the present experimental upper limit. In addition to θ13\theta_{13} and δCP\delta_{CP}, the experiment has great potential for precise measurements of most other parameters in the neutrino mixing matrix including Δm322\Delta m^2_{32}, sin22θ23\sin^2 2\theta_{23}, Δm212×sin2θ12\Delta m^2_{21}\times \sin 2 \theta_{12}, and the mass ordering of neutrinos through the observation of the matter effect in the νμνe\nu_\mu \to \nu_e appearance channel.Comment: 12 pages, 10 figure

    A consistent treatment for pion form factors in space-like and time-like regions

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    We write down some relevant matrix elements for the scattering and decay processes of the pion by considering a quark-meson vertex function. The pion charge and transition form factors FπF_\pi, FπγF_{\pi\gamma}, and FπγF_{\pi\gamma^*} are extracted from these matrix elements using a relativistic quark model on the light-front. We found that, the form factors FπF_\pi and FπγF_{\pi\gamma} in the space-like region agree well with experiment. Furthermore, the branching ratios of all observed decay modes of the neutral pion, that are related to the form factors FπγF_{\pi\gamma} and FπγF_{\pi\gamma^*} in the time-like region, are all consistent with the data as well. Additionally, FπF_\pi in the time-like region, which deals with the nonvalence contribution, is also discussed.Comment: 24 pages, 6 figures, to appear in Phys. Rev.

    Higgs-Boson Decay to Four Fermions Including a Single Top Quark Below ttˉt \bar t Threshold

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    The rare decay modes Higgs \rightarrow four light fermions, and Higgs \rightarrow single top-quark + three light fermions for mt<MH<2mtm_t<M_H<2m_t, are presented, and phenomenologically interpreted. The angular correlation between fermion planes is presented as a test of the spin and intrinsic parity of the Higgs particle. In Higgs decay to single top, two tree-level graphs contribute in the standard model (SM); one couples the Higgs to W+W(gMW)W^+W^-(\sim gM_W), and one to t\bar t(\sim g_{top\;yukawa}=m_t/246\GeV). The large Yukawa coupling for m_t>100\GeV makes the second amplitude competitive or dominant for most MH,mtM_H,m_t values. Thus the Higgs decay rate to single top directly probes the SM universal mechanism generating both gauge boson and fermion masses, and offers a means to infer the Higgs-ttˉt \bar t Yukawa coupling when HttˉH\rightarrow t \bar t is kinematically disallowed. We find that the modes ppXttˉ(HtbˉW())pp\rightarrow Xt\bar t(H\rightarrow t\bar b W^{(*)}) at the SSC, and e+eZorννˉ+(HtbˉW())e^+ e^-\rightarrow Z\,or\,\nu\bar{\nu} + (H\rightarrow t\bar b W^{(*)}) at future high energy, high luminosity colliders, may be measureable if 2mt2m_t is not too far above MHM_H. We classify non-standard Higgses as gaugeo-phobic, fermio-phobic or fermio-philic, and discuss the Higgs\rightarrow single top rates for these classes.Comment: 30 pages, 6 figures (figures available upon request); VAND-TH-93/

    Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF

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    The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described

    The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

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    The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure

    An investigation of thermodynamics, microscopic structure, depolarized Rayleigh scattering, and collision dynamics in Xe-N-2 supercritical mixtures

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    We would like to dedicate this work to the late Professor W. A. Steele (W.A.S.), Penn State University, USA. NATO Research-Project SA 5-2-05(CRG 950087) JARC (97) 288 is acknowledged for project funding to J.S., H.V. and W.A.S. The Greek State Scholarships Foundation (IKY) is acknowledged for an award based on performance to S. M. This work was supported by computational time granted from the Greek Research & Technology Network (GRNET) in the National HPC facility ARIS. The CPU time of the Computing Centre of the University of Athens (Greece) is gratefully acknowledged. This research utilized Queen Mary’s Mid-Plus computational facilities, supported by QMUL Research-IT and funded by EPSRC grant EP/K000128/1. J.K. acknowledges financial support from the NSF Grant No. CHE-1565872 to Millard Alexander
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