249 research outputs found

    The origins of cosmic rays and quantum effects on gravity

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    The energy spectrum of primary cosmic rays is explained by particles emitted during a thermal expansion of explosive objects inside and near the galaxy, remnants of which may be supernova and/or active talaxies, or even stars or galaxies that disappeared from our sight after the explosion. A power law energy spectrum for cosmic rays, E to the (-alpha -1, is obtained from an expansion rate T is proportional to R to the alpha. Using the solution of the Einstein equation, we obtain a spectrum which agrees very well with experimental data. The implication of an inflationary early universe on the cosmic ray spectrum is also discussed. It is also suggested that the conflict between this model and the singularity theorem in classical general relativity may be eliminated by quantum effects

    High energy cosmic rays, gamma rays and neutrinos from AGN

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    The author reviews a model for the emission of high energy cosmic rays, gamma-rays and neutrinos from AGN (Active Galactic Nuclei) that he has proposed since 1985. Further discussion of the knee energy phenomenon of the cosmic ray energy spectrum requires the existence of a heavy particle with mass in the knee energy range. A possible method of detecting such a particle in the Pierre Auger Project is suggested. Also presented is a relation between the spectra of neutrinos and gamma-rays emitted from AGN. This relation can be tested by high energy neutrino detectors such as ICECUBE, the Mediterranean Sea Detector and possibly by the Pierre Auger Project.Comment: 4 pages, no figure

    Exotic hadrons in s-wave chiral dynamics

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    We study s-wave scattering of a hadron and a Nambu-Goldstone boson induced by the model-independent low energy interaction in the flavor SU(3) symmetric limit. Establishing the general structure of the low energy interaction based on group theoretical arguments, we find that the interaction in the exotic channels are in most cases repulsive, and that for possible attractive channels the interaction strengths are weak and uniquely given independent of channel. Solving the scattering problem with this interaction, we show that the attraction in the exotic channels is not strong enough to generate a bound state from the physically known target hadrons. We also find that there are no attractive interaction in the exotic channels in large Nc limit.Comment: RevTeX4, 4 pages, 1 figure, 2 tables, typos correcte

    Low lying axial-vector mesons as dynamically generated resonances

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    We make a theoretical study of the s-wave interaction of the nonet of vector mesons with the octet of pseudoscalar mesons starting from a chiral invariant Lagrangian and implementing unitarity in coupled channels. By looking for poles in the unphysical Riemann sheets of the unitarized scattering amplitudes, we get two octets and one singlet of axial-vector dynamically generated resonances. The poles found can be associated to most of the low lying axial-vector resonances quoted in the Particle Data Book: b1(1235)b_1(1235), h1(1170)h_1(1170), h1(1380)h_1(1380), a1(1260)a_1(1260), f1(1285)f_1(1285) and two poles to the K1(1270)K_1(1270) resonance. We evaluate the couplings of the resonances to the VPVP states and the partial decay widths in order to reinforce the arguments in the discussion.Comment: 31 pages, 12 figures, Accepted for publication in Phys.Rev.

    Study of exotic hadrons in S-wave scatterings induced by chiral interaction in the flavor symmetric limit

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    We study s-wave bound states of a hadron and a light pseudoscalar meson induced by the Weinberg-Tomozawa (WT) interaction in the flavor SU(3) symmetric limit. The WT interaction is a driving force to generate quasibound states dynamically in the chiral unitary approaches. The strength and sign of the WT interaction are determined only by the group theoretical structure of the target hadrons, and we present a general expression of the strengths for the flavor SU(3) case. We show that, for the channels which are more exotic than the target, the interaction is repulsive in most cases, and the strength of the attractive interaction is universal for any possible target states. We demonstrate that the attractive coupling is not strong enough to generate an exotic state from the physically known masses of target hadrons. In addition, we also find a nontrivial Nc dependence of the coupling strengths. We show that the channels which are attractive at Nc=3 changes into repulsive ones for large Nc, and, therefore, no attractive interaction exists in exotic channels in the large-Nc limit.Comment: RevTeX4, 16 pages, 5 figure, 6 tables, This manuscript is a full paper of Phys. Rev. Lett. 97, 192002 (hep-ph/0609014), typos corrected, final versio

    Evaluation of the Axial Vector Commutator Sum Rule for Pion-Pion Scattering

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    We consider the sum rule proposed by one of us (SLA), obtained by taking the expectation value of an axial vector commutator in a state with one pion. The sum rule relates the pion decay constant to integrals of pion-pion cross sections, with one pion off the mass shell. We remark that recent data on pion-pion scattering allow a precise evaluation of the sum rule. We also discuss the related Adler--Weisberger sum rule (obtained by taking the expectation value of the same commutator in a state with one nucleon), especially in connection with the problem of extrapolation of the pion momentum off its mass shell. We find, with current data, that both the pion-pion and pion-nucleon sum rules are satisfied to better than six percent, and we give detailed estimates of the experimental and extrapolation errors in the closure discrepancies.Comment: Plain TeX file;minor changes; version to be published in Pys. Rev. D; corrected refs.12,1

    Two components of dark matter in the DAMA data

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    It is shown that the DAMA data indicate two dark matter components, one that circulates around the galactic center (GC) and another that is emitted from the GC. From the location of the maximum yearly variation, one can compute the ratio of the two components.Comment: 4 pages, no figur

    Interplay of the Chiral and Large N_c Limits in pi N Scattering

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    Light-quark hadronic physics admits two useful systematic expansions, the chiral and 1/N_c expansions. Their respective limits do not commute, making such cases where both expansions may be considered to be especially interesting. We first study pi N scattering lengths, showing that (as expected for such soft-pion quantities) the chiral expansion converges more rapidly than the 1/N_c expansion, although the latter nevertheless continues to hold. We also study the Adler-Weisberger and Goldberger-Miyazawa-Oehme sum rules of pi N scattering, finding that both fail if the large N_c limit is taken prior to the chiral limit.Comment: 10 pages, ReVTe

    Residual interaction effects on deeply bound pionic states in Sn and Pb isotopes

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    We have studied the residual interaction effects theoretically on the deeply bound pionic states in Pb and Sn isotopes. We need to evaluate the residual interaction effects carefully in order to deduce the nuclear medium effects for pion properties, which are believed to provide valuable information on nuclear chiral dynamics. The s- and p-wave π−N\pi-N interactions are used for the pion-nucleon residual interactions. We show that the complex energy shifts are around [(10-20)+i(2-7)]keV for 1s states in Sn, which should be taken into account in the analyses of the high precision data of deeply bound pionic 1s1s states in Sn isotopes.Comment: REVTEX4, 6 pages, 5 tables, Submitted to Phys. Rev. C, Some explanations are added in Version

    Supersymmetry and parastatistics

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    An analysis is made of the supersymmetry of parafields in Wess-Zumino-type models with two cases in which parabosons and parafermions form a supermultiplet. In case one the symmetry is realized by either the normal superalgebra or an infinite Lie algebra as in ordinary supersymmetry. In case two the infinite Lie algebra is intrinsic to the supersymmetry. With appropriate symmetry breaking, formulations of these types may be used to explain the generation problem by postulating unobserved parabosons as supersymmetric partners. The relevance to these models of an infinite Lie algebra constructed from supersymmetry is mentioned.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25130/1/0000563.pd
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