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Related papers: A Model for the Optical/IR Emission from Magnetars

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We show that magnetar models for ULX behaviour have serious internal inconsistencies. The magnetic fields required to increase the limiting luminosity for radiation pressure above the observed (assumed isotropic) luminosities are completely…

High Energy Astrophysical Phenomena · Physics 2023-09-25 Jean-Pierre Lasota , Andrew King

X-ray pulsars (XRPs) consist of a magnetized neutron star (NS) and an optical donor star. The NS accretes matter from the donor star producing pulsed X-ray emission. In most cases the donor stars are Be stars, and accretion is episodic,…

High Energy Astrophysical Phenomena · Physics 2025-09-26 Shan-Shan Weng , Xiao-Tian Xu , Han-Long Peng , Yu-Jing Xu , Yan Zhang , Ying-Han Mao , Xiang-Dong Li , Jing-Zhi Yan , Qing-Zhong Liu

A simple and well known model for thermal radiation spectra from a magnetized neutron star is further studied. The model assumes that the star is internally isothermal and possesses dipole magnetic field (B <= 1e14 G) in the outer…

High Energy Astrophysical Phenomena · Physics 2021-10-27 D. G. Yakovlev

It is a well-known fact that compact gravitating objects admit bound state configurations for massive bosonic fields. In this work we describe a new class of superradiant instabilities of axion bound states in neutron star magnetospheres.…

High Energy Physics - Phenomenology · Physics 2019-10-29 Francesca V. Day , Jamie I. McDonald

Abridged) We model the X-ray properties of millisecond pulsars (MSPs) by considering hot spot emission from a weakly magnetized rotating neutron star (NS) covered by an optically-thick hydrogen atmosphere. We investigate the limitations of…

Astrophysics · Physics 2009-11-13 Slavko Bogdanov , Jonathan E. Grindlay , George B. Rybicki

Recent observations have detected a number of young pulsars from the power peak in the gamma-ray band to the incoherent photon peak in the optical/IR. We have made progress on the multiwavelength phenomenology of pulsar emission and…

Astrophysics · Physics 2007-05-23 Roger W. Romani

Anomalous X-ray pulsars and soft gamma repeaters have recently emerged as a unified class of neutron stars, identified by dramatic X-ray and gamma-ray outbursts and via luminous X-ray pulsations, both thought to be powered by the decay of…

High Energy Astrophysical Phenomena · Physics 2015-05-20 C. -Y. Ng , V. M. Kaspi

Hard, non-thermal, persistent pulsed X-ray emission extending between 10 keV and $\sim 150$ keV has been observed in nearly ten magnetars. For inner-magnetospheric models of such emission, resonant inverse Compton scattering of soft thermal…

High Energy Astrophysical Phenomena · Physics 2018-02-28 Zorawar Wadiasingh , Matthew G. Baring , Peter L. Gonthier , Alice K. Harding

We suggest that some observational features of high-energy radiation from pulsars should be explained in terms of three dimensional geometric models, e.g. the phase-resolved X-ray and $\gamma$-ray spectra and the energy dependent light…

Astrophysics · Physics 2009-11-10 K. S. Cheng

A two-dimensional electrodynamic model is used to study particle acceleration and non-thermal emission mechanisms in the pulsar magnetospheres. We solve distribution of the accelerating electric field with the emission process and the…

Astrophysics · Physics 2009-11-13 J. Takata , H. -K. Chang , S. Shibata

The hard X-ray emission from magnetars and other isolated neutron stars remains under-explored. An instrument with higher sensitivity to hard X-rays is critical to understanding the physics of neutron star magnetospheres and also the…

Energy losses from isolated neutron stars are commonly attributed to the emission of electromagnetic radiation from a rotating point-like magnetic dipole in vacuum. This emission mechanism predicts a braking index $n=3$, which is not…

High Energy Astrophysical Phenomena · Physics 2016-12-14 Adam Rogers , Samar Safi-Harb

Thermal surface radiation has been detected with X-ray instruments for several neutron stars with high spectral, spatial and timing resolution. These observations allow for direct study of fundamental properties of the source, but require…

Astrophysics · Physics 2007-05-23 D. A. Lloyd

Axions can be copiously produced in localized regions of neutron star magnetospheres where the ambient plasma is unable to efficiently screen the induced electric field. As these axions stream away from the neutron star they can resonantly…

High Energy Physics - Phenomenology · Physics 2023-07-26 Dion Noordhuis , Anirudh Prabhu , Samuel J. Witte , Alexander Y. Chen , Fábio Cruz , Christoph Weniger

There is an increasing theoretical and observational evidence that the external magnetic field of magnetars may contain a toroidal component, likely of the same order of the poloidal one. Such "twisted magnetospheres" are threaded by…

High Energy Astrophysical Phenomena · Physics 2009-11-13 L. Pavan , R. Turolla , S. Zane , L. Nobili

In this study we propose a new generic model for QPOs based on oscillation modes of neutron star magnetospheres. We argue that the interaction of the accretion disk with the magnetosphere can excite resonant shear Alfven waves in a region…

Astrophysics · Physics 2007-05-23 Vahid Rezania , John C. Samson , Peter Dobias

A model is proposed for the observed combination of power-law and thermal emission of keV X-rays from rotationally powered pulsars. For gamma-ray pulsars with accelerators very many stellar radii above the neutron star surface, 100 MeV…

Astrophysics · Physics 2009-10-30 F. Y. -H. Wang , M. Ruderman , J. P. Halpern , T. Zhu

In this paper, we discuss our first attempts to model the broadband persistent emission of magnetars within a self consistent, physical scenario. We present the predictions of a synthetic model that we calculated with a new Monte Carlo 3-D…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Silvia Zane , Roberto Turolla , Luciano Nobili , Nanda Rea

The $Fermi$-LAT has revealed that rotation powered millisecond pulsars (MSPs) are a major contributor to the Galactic $\gamma$-ray source population. Such pulsars may also be important in modeling the quiescent state of several low mass…

High Energy Astrophysical Phenomena · Physics 2015-06-03 J. Takata , K. S. Cheng , R. E. Taam

We discuss growing evidence that pulsar high energy is emission is generated via Inverse Compton mechanism. We reproduce the broadband spectrum of Crab pulsar, from UV to very high energy gamma-rays - nearly ten decades in energy, within…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Maxim Lyutikov