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Related papers: Charge densities above pulsar polar caps

200 papers

We study on the self-consistency of the pulsar polar cap model, i.e., the problem of whether the field-aligned electric field is screened by electron-positron pairs that are injected beyond the pair production front. We solve the…

Astrophysics · Physics 2009-11-07 S. Shibata , J. Miyazaki , F. Takahara

Recent $\gamma$-ray observations suggest that the particle acceleration occurs at the outer region of the pulsar magnetosphere. The magnetic field lines in the outer acceleration region (OAR) are connected to the neutron star surface (NSS).…

High Energy Astrophysical Phenomena · Physics 2016-09-21 Shota Kisaka , Katsuaki Asano , Toshio Terasawa

Rough estimates and upper limits on current and particle densities form the basis of most of the canonical pulsar models. Whereas the surface of the rotating neutron star is capable of supplying sufficient charges to provide a current that,…

Astrophysics · Physics 2007-05-23 A. Jessner , H. Lesch , T. Kunzl

We present the first self-consistent global simulations of pulsar magnetospheres with operating $e^\pm$ discharge. We focus on the simple configuration of an aligned or anti-aligned rotator. The star is spun up from zero (vacuum) state to a…

High Energy Astrophysical Phenomena · Physics 2014-10-28 Alexander Y. Chen , Andrei M. Beloborodov

The possibility of a neutron m=2-superfluid in the interior of neutron stars is investigated. This pairing state is energetically favoured in strong magnetic fields ($H\sim 10^{16}-10^{17}$ G). Because of the node in the angular-dependent…

Astrophysics · Physics 2016-08-30 Ch. Schaab , F. Weber , M. K. Weigel

The study of physical processes associated with particle acceleration in the open field line region above the polar cap (PC) of an isolated neutron star (NS) plays a fundamental role in our understanding and interpretation of high-energy…

Astrophysics · Physics 2007-05-23 Alice K. Harding , Alexander G. Muslimov

We analytically study the properties of the electromagnetic field in vacuum around close binary compact stars containing at least one neutron star. We show that the orbital motion of the neutron star induces high multipole modes of the…

High Energy Astrophysical Phenomena · Physics 2022-09-16 Tomoki Wada , Masaru Shibata , Kunihito Ioka

Based on the formalism by Kaminker et al. (Astron. Astrophys. 343 (1999) 1009) we derive an analytic approximation for neutrino-pair bremsstrahlung emissivity due to scattering of electrons by atomic nuclei in the neutron star crust of any…

Solar and Stellar Astrophysics · Physics 2015-06-23 D. D. Ofengeim , A. D. Kaminker , D. G. Yakovlev

We consider the details of the QED processes that create electron-positron pairs in magnetic fields approaching and exceeding 10^{14} G. The formation of free and bound pairs is addressed, and the importance of positronium dissociation by…

Astrophysics · Physics 2009-11-13 Christopher Thompson

We investigate the thermal emission from magnetic neutron star surfaces in which the cohesive effects of the magnetic field have produced the condensation of the atmosphere and the external layers. This may happen for sufficiently cool…

Astrophysics · Physics 2015-06-24 J. F. Perez--Azorin , J. A. Miralles , J. A. Pons

The origin of very energetic charged particles and the production of very high-energy (VHE) gamma-ray emission remains still a challenging issue in modern pulsar physics. By applying a toy model, we explore the acceleration of co-rotating…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Zaza Osmanov , Frank M. Rieger

The luminosity of X-ray pulsars powered by accretion onto magnetized neutron stars covers a wide range over a few orders of magnitude. The brightest X-ray pulsars recently discovered as pulsating ultraluminous X-ray sources reach accretion…

High Energy Astrophysical Phenomena · Physics 2019-05-29 Alexander A. Mushtukov , Igor S. Ognev , Dmitrij I. Nagirner

We investigate the self-consistent electrodynamic structure of a particle accelerator in the Crab pulsar magnetosphere on the two-dimensional poloidal plane, solving the Poisson equation for the electrostatic potential together with the…

Astrophysics · Physics 2008-11-26 Kouichi Hirotani

Models of pulsar radio emission that are based on an inner accelerating region require the existence of very strong and small scale surface magnetic field structures at or near the canonical polar cap. The aim of this paper is to identify a…

Solar and Stellar Astrophysics · Physics 2015-06-16 U. Geppert , J. Gil , G. Melikidze

Pair cascades in polar cap regions of neutron stars are considered to be an essential process in various models of coherent radio emissions of pulsars. The cascades produce pair plasma bunch discharges in quasi-periodic spark events. The…

High Energy Astrophysical Phenomena · Physics 2024-11-06 Jan Benáček , Andrey Timokhin , Patricio A. Muñoz , Axel Jessner , Tatiana Rievajová , Martin Pohl , Jörg Büchner

We investigate a stationary particle acceleration zone in the outer magnetosphere of a spinning neutron star. The charge depletion due to a global current causes a large electric field along the magnetic field lines. Migratory electrons…

Astrophysics · Physics 2009-10-31 Kouichi Hirotani , Shinpei Shibata

A time-dependent model for pair creation in a pulsar magnetosphere is developed. It is argued that the parallel electric field that develops in a charge-starved region (a gap) of a pulsar magnetosphere oscillates with large amplitude.…

Astrophysics · Physics 2009-11-10 Amir Levinson , Don Melrose , Alex Judge , Qinghuan Luo

Current closure in the pulsar magnetosphere holds the key to its structure. We must determine not only the global electric circuit, but also the source of its electric charge carriers. We address this issue with the minimum number of…

High Energy Astrophysical Phenomena · Physics 2018-10-17 Ioannis Contopoulos

Over the last four decades, persistent and flaring emission of magnetars observed by various telescopes has provided us with a suite of light curves and spectra in soft and hard X-rays, with no emission yet detected above around 1 MeV.…

High Energy Astrophysical Phenomena · Physics 2019-04-17 Kun Hu , Matthew G. Baring , Zorawar Wadiasingh , Alice K. Harding

Unpulsed, high-energy emission from pulsar binaries can be attributed to the interaction of a pulsar wind with that of a companion star. At the shock between the outflows, particles carried away from the pulsar magnetosphere are accelerated…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Iwona Mochol , John G. Kirk