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Related papers: Gamma-ray Pulsars in a Modified Polar Cap Scenario

200 papers

We report observations of PSR's 0740-28, 1737-30, 1822-09, 1915+13 and 1916+14 with ROSAT. In the 0.1-2.1 keV range upper limits to luminosity are derived for power law and blackbody spectra, using a range of $N_{H}$ estimates. The upper…

Astrophysics · Physics 2007-05-23 M. A. Alpar , O. H. Guseinov , U. Kiziloglu , H. Ogelman

If the binding energy of the pulsar's surface is not so high (the case of a neutron star), both the negative and positive charges will flow out freely from the surface of the star. The annular free flow model for $\gamma$-ray emission of…

Astrophysics · Physics 2020-06-03 G. J. Qiao , K. J. Lee , B. Zhang , H. G. Wang , R. X. Xu

We report on an XMM-Newton observation of the accreting millisecond pulsar, IGR J17511-3057. Pulsations at 244.8339512(1) Hz are observed with an RMS pulsed fraction of 14.4(3)%. A precise solution for the P_orb=12487.51(2)s binary system…

High Energy Astrophysical Phenomena · Physics 2015-05-19 A. Papitto , A. Riggio , T. Di Salvo , L. Burderi , A. D'Aì , R. Iaria , E. Bozzo , M. T. Menna

I present an analysis of the XMM-Newton observations of four millisecond pulsars, J0437-4715, J2124-3358, J1024-0719, and J0034-0534. The new data provide strong evidence of thermal emission in the X-ray flux detected from the first three…

Astrophysics · Physics 2010-11-11 Vyacheslav E. Zavlin

We examine the published light curves (LCs) of 117 X-ray binary pulsars, focusing on the dependence of their light curves on the observed energy bands. It is found that the energy dependence of the LCs appears only when the X-ray luminosity…

Astrophysics · Physics 2015-05-13 S. Karino

A number of previous papers have developed an ion-proton theory of the pulsar polar cap. The basic equations summarizing this are given here with the results of sets of model step-to-step calculations of pulse-precursor profiles. The nature…

High Energy Astrophysical Phenomena · Physics 2020-01-08 P B Jones

A growing number of early Be stars discovered in X-ray surveys exhibit X-ray luminosities intermediate between those of normal stars and those of most Be/X-ray binaries in quiescence. Their X-ray spectra are also much harder than those of…

Anomalous X-ray pulsars and soft gamma repeaters are slowly rotating, young, and isolated neutron stars exhibiting sporadic outbursts and high X-ray quiescent luminosities. They are believed to be powered by ultrastrong magnetic fields,…

High Energy Astrophysical Phenomena · Physics 2021-06-02 Tushar Mondal

The spectra of several X-ray binary pulsars display a clear soft excess, which in most cases can be described with a blackbody model, above the main power-law component. While in the high-luminosity sources it is usually characterized by…

High Energy Astrophysical Phenomena · Physics 2015-05-13 N. La Palombara , L. Sidoli , P. Esposito , A. Tiengo , S. Mereghetti

Forty years after the discovery of rotation-powered pulsars, we still do not understand many aspects of their pulsed emission. In the last few years there have been some fundamental developments in acceleration and emission models. I will…

Astrophysics · Physics 2007-10-19 Alice K. Harding

We study plasma flows above pulsar polar caps using time-dependent simulations of plasma particles in the self-consistent electric field. The flow behavior is controlled by the dimensionless parameter alpha=(j/c rho_GJ) where j is the…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Alexander Y. Chen , Andrei M. Beloborodov

The Fermi Gamma-Ray Space Telescope has discovered many gamma-ray pulsars, both as radio-loud objects and radio-quiet or radio-weak pulsars that have been identified through blind period searches. The latter presumably have gamma-ray beams…

High Energy Astrophysical Phenomena · Physics 2010-02-02 Marco Pierbattista , Isabelle Grenier , Alice Harding , Peter Gonthier

Pulsars with compact companions in close eccentric orbits are unique laboratories for testing general relativity and alternative theories of gravity. Moreover, they are excellent targets for future gravitational wave experiments like LISA…

Solar and Stellar Astrophysics · Physics 2015-05-20 J. Antoniadis , C. G. Bassa , N. Wex , M. Kramer , R. Napiwotzki

PSR 1259-63 is a radio pulsar orbiting a Be star in a highly eccentric orbit. Soft and hard X-rays are observed from this binary system. We apply the shock powered emission model to this system. The collision of the pulsar and Be star winds…

Astrophysics · Physics 2015-06-24 K. Murata , H. Tamaki , H. Maki , N. Shibazaki

The high-energy gamma-ray emission discovered using the H.E.S.S. telescopes from the binary system PSR B1259 -63, is modelled using an extension of the approach that successfully predicted it. We find that the simultaneous INTEGRAL and…

Astrophysics · Physics 2016-08-30 J. G. Kirk , Lewis Ball , S. Johnston

We present the results from the analysis of the broad-band X-ray spectra of 5 Anomalous X-ray Pulsars (AXPs) and Soft $\gamma$-ray Repeaters (SGRs). We fit their Suzaku and INTEGRAL spectra with models appropriate for the X-ray emission…

High Energy Astrophysical Phenomena · Physics 2015-10-28 A. Zezas , J. E. Trümper , N. D. Kylafis

Linear polarization in X- and gamma-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization…

Both leptonic and hadronic emission processes may contribute to blazar jet emission; which dominates in blazars's high energy emission component remains an open question. Some intermediate synchrotron peaked blazars transition from their…

High Energy Astrophysical Phenomena · Physics 2022-06-01 Abel L. Peirson , Ioannis Liodakis , Roger W. Romani

The polarization of recoil photon ($\gamma'$) in the non-linear Compton process $e + \vec L \to \vec \gamma' +e'$ in the interaction of a relativistic electron with a linearly polarized laser beam ($\vec L$) is studied within the Furry…

High Energy Physics - Phenomenology · Physics 2024-03-27 A. I. Titov

Complementary views of galaxy clusters in the radio synchrotron, hard X-ray inverse Compton, and high-energy gamma-ray regimes are critical in calibrating them as high-precision cosmological probes. We present predictions for scaling…

Astrophysics · Physics 2009-11-13 Christoph Pfrommer
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