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Related papers: Oscillating pulsar polar gaps

200 papers

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

Electron-positron pair creation in a standing wave is explored using a parameter-free quantum kinetic equation. Field strengths and frequencies corresponding to modern optical lasers induce a material polarisation of the QED vacuum, which…

Nuclear Theory · Physics 2010-03-04 D. B. Blaschke , A. V. Prozorkevich , C. D. Roberts , S. M. Schmidt , S. A. Smolyansky

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

The expansion of a charge-neutral cloud of electrons and positrons with the temperature 1 MeV into an unmagnetized ambient plasma is examined with a 2D particle-in-cell (PIC) simulation. The pair outflow drives solitary waves in the ambient…

High Energy Astrophysical Phenomena · Physics 2018-08-01 ME Dieckmann , A Alejo , G Sarri

We have studied the linear dispersion relation for Langmuir waves in plasmas of very high density, based on the Dirac-Heisenberg-Wigner formalism. The vacuum contribution to the physical observables leads to ultra-violet divergences, that…

Plasma Physics · Physics 2022-04-20 H. Al-Naseri , G. Brodin

We study the efficiency of pair production in polar caps of young pulsars under a variety of conditions to estimate the maximum possible multiplicity of pair plasma in pulsar magnetospheres. We develop a semi-analytic model for calculation…

High Energy Astrophysical Phenomena · Physics 2018-03-28 A. N. Timokhin , A. K. Harding

We consider the motion of a charge in a large amplitude electrostatic wave with a triangular wave form relevant to an oscillating model of a pulsar magnetosphere. The (one-dimensional) orbit of a particle in such a wave is found exactly in…

High Energy Astrophysical Phenomena · Physics 2011-02-11 D. B. Melrose , M. Z. Rafat , Q. Luo

There has been growing speculation that a pair density wave state is a key component of the phenomenology of the pseudogap phase in the cuprates. Recently, direct evidence for such a state has emerged from an analysis of scanning tunneling…

Superconductivity · Physics 2018-07-04 M. R. Norman , J. C. Seamus Davis

We present the results of the calculation of the electron-positron pair creation probability by the circularly polarized electromagnetic wave during its propagation in underdense collisionless plasmas. The dependence of the probability on…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. S. Bulanov

Following the early paper of Goldreich & Julian (1969), polar-cap models have usually assumed that the closed sector of a pulsar magnetosphere corotates with the neutron star. Recent work by Melrose & Yuen has been a reminder that in an…

High Energy Astrophysical Phenomena · Physics 2015-09-09 P. B. Jones

We study low energy quantum oscillations of electron gas in plasma. It is shown that two electrons participating in these oscillations acquire additional negative energy when they interact by means of a virtual plasmon. The additional…

Plasma Physics · Physics 2009-02-27 Maxim Dvornikov

We study self-consistency for the pulsar polar cap model. In general, there will remain an unscreened electric field at the pair production front (PPF). We have derived the condition of electric field screening by pairs in the presence of…

Astrophysics · Physics 2007-05-23 S. Shibata , J. Miyazaki , F. Takahara

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

Coherent radio emission from pulsars originates from excited plasma waves in an ultra-relativistic and strongly magnetized electron-positron pair plasma streaming along the open magnetic field lines of the pulsar. Traditional coherent radio…

High Energy Astrophysical Phenomena · Physics 2022-08-16 Sk. Minhajur Rahaman , Dipanjan Mitra , George I. Melikidze

A new nonlinear electromagnetic wave mode in a plasma is reported. Its existence depends on the interaction of an intense circularly polarized electromagnetic wave with a plasma, where quantum electrodynamical photon--photon scattering is…

Plasma Physics · Physics 2015-06-26 Lennart Stenflo , Gert Brodin , Mattias Marklund , Padma K. Shukla

Pulsar magnetospheres are thought to be filled with electron-positron plasma generated in pair cascades. The driving mechanism of these cascades is the emission of gamma-ray photons and their conversion into pairs via Quantum…

High Energy Astrophysical Phenomena · Physics 2021-09-30 Fábio Cruz , Thomas Grismayer , Alexander Y. Chen , Anatoly Spitkovsky , Luis O. Silva

We study the magnetospheric activity in the polar cap region of pulsars under stellar oscillations. The toroidal oscillation of the star propagates into the magnetosphere, which provides additional voltage due to unipolar induction, changes…

High Energy Astrophysical Phenomena · Physics 2015-01-27 Meng-Xiang Lin , Ren-Xin Xu , Bing Zhang

It is shown that pulsar radio emission can be generated effectively through a streaming motion in the polar-cap regions of a pulsar magnetosphere causing nonresonant growth of waves that can escape directly. As in other beam models, a…

Astrophysics · Physics 2009-11-07 M. Gedalin , E. Gruman , D. B. Melrose

Expanding on the comment by Lyne et al (2017), that intermittent pulsars tend to congregate near a stripe in the logarithmic period versus period-derivative diagram, representing a small range of polar cap electric potential, as well as the…

High Energy Astrophysical Phenomena · Physics 2021-11-24 Fan Zhang

We discuss the creation of electron-positron cascades in the context of pulsar polar cap acceleration models and derive several useful analytic and semi-analytic results for the spatial extent and energy response of the cascade. Instead of…

Astrophysics · Physics 2009-11-06 J. A. Hibschman , J. Arons