3,280 research outputs found

    Pulse Profiles, Spectra and Polarization Characteristics of Non-Thermal Emissions from the Crab-Like Pulsars

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    We discuss non-thermal emission mechanism of the Crab-like pulsars with both a two-dimensional electrodynamical study and a three-dimensional model. We investigate the emission process in the outer gap accelerator. In the two-dimensional electrodynamical study, we solve the Poisson equation of the accelerating electric field in the outer gap and the equation of motion of the primary particles with the synchrotron and the curvature radiation process and the pair-creation process. We show a solved gap structure which produces a consistent gamma-ray spectrum with EGRET observation. Based on the two-dimensional model, we conduct a three-dimensional emission model to calculate the synchrotron and the inverse-Compton processes of the secondary pairs produced outside the outer gap. We calculate the pulse profiles, the phase-resolved spectra and the polarization characteristics in optical to γ\gamma-ray bands to compare the observation of the Crab pulsar and PSR B0540-69. For the Crab pulsar, we find that the outer gap geometry extending from near the stellar surface to near the light cylinder produces a complex morphology change of the pulse profiles as a function of the photon energy. This predicted morphology change is quite similar with that of the observations. The calculated phase-resolved spectra are consistent with the data through optical to the γ\gamma-ray bands. We demonstrate that the 10∼\sim20 % of the polarization degree in the optical emissions from the Crab pulsar and the Vela pulsar are explained by the synchrotron emissions with the particle gyration motion.Comment: 39 pages, 11 figures, Accepted for publication in Ap

    Effective Lagrangian for a Technicolor Model without Exact Custodial Symmetry

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    Effective Lagrangian including technimesons is constructed for a realistic one-family Technicolor model without exact custodial symmetry. Tree level contribution to oblique correction parameters SS and UU due to spin 1 technimesons are computed with the effective Lagrangian. An isospin breaking term which is associated with technilepton vector mesons gives a negative contribution to the electroweak radiative correction parameter SS due to mixing between I=0I=0 and I=1I=1 vector mesons. UU receives non-zero contribution due to exotic left-handed charged vector mesons and its sign can be both negative and positive.Comment: 30 pages plus 1 table and 4 figures (7 postscript files append.), Latex, (HUPD-9406

    BRST approach to Lagrangian construction for bosonic continuous spin field

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    We formulate the conditions defining the irreducible continuous spin representation of the four-dimensional Poincar\'e group based on spin-tensor fields with dotted and undotted indices. Such a formulation simplifies analysis of the Bargmann-Wigner equations and reduces the number of equations from four to three. Using this formulation we develop the BRST approach and derive the covariant Lagrangian for the continuous spin fields.Comment: 10 pages, v2 references adde

    Alfven seismic vibrations of crustal solid-state plasma in quaking paramagnetic neutron star

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    Magneto-solid-mechanical model of two-component, core-crust, paramagnetic neutron star responding to quake-induced perturbation by differentially rotational, torsional, oscillations of crustal electron-nuclear solid-state plasma about axis of magnetic field frozen in the immobile paramagnetic core is developed. Particular attention is given to the node-free torsional crust-against-core vibrations under combined action of Lorentz magnetic and Hooke's elastic forces; the damping is attributed to Newtonian force of shear viscose stresses in crustal solid-state plasma. The spectral formulae for the frequency and lifetime of this toroidal mode are derived in analytic form and discussed in the context of quasi-periodic oscillations of the X-ray outburst flux from quaking magnetars. The application of obtained theoretical spectra to modal analysis of available data on frequencies of oscillating outburst emission suggests that detected variability is the manifestation of crustal Alfven's seismic vibrations restored by Lorentz force of magnetic field stresses.Comment: 10 pages, 10 figure

    A NuSTAR Observation of the Gamma-ray Emitting Millisecond Pulsar PSR J1723-2837

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    We report on the first NuSTAR observation of the gamma-ray emitting millisecond pulsar binary PSR J1723-2837. X-ray radiation up to 79 keV is clearly detected and the simultaneous NuSTAR and Swift spectrum is well described by an absorbed power-law with a photon index of ~1.3. We also find X-ray modulations in the 3-10 keV, 10-20 keV, 20-79 keV, and 3-79 keV bands at the 14.8-hr binary orbital period. All these are entirely consistent with previous X-ray observations below 10 keV. This new hard X-ray observation of PSR J1723-2837 provides strong evidence that the X-rays are from the intrabinary shock via an interaction between the pulsar wind and the outflow from the companion star. We discuss how the NuSTAR observation constrains the physical parameters of the intrabinary shock model.Comment: Accepted for publication in ApJ. 5 pages, 3 figure
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