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Related papers: Hard X-ray Emission from Magnetars : A Case Study …

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Magnetars form a special population of neutron stars with strong magnetic fields and long spin periods. About 30 magnetars and magnetar candidates known currently are probably isolated. But the possibility that magnetars are in binaries…

High Energy Astrophysical Phenomena · Physics 2022-02-02 Kun Xu , Xiang-Dong Li , Zhe Cui , Qiao-Chu Li , Yong Shao , Xilong Liang , Jifeng Liu

Non-thermal quiescent X-ray emission extending between 10 keV and around 150 keV has been seen in about 10 magnetars by RXTE, INTEGRAL, Suzaku, NuSTAR and Fermi-GBM. For inner magnetospheric models of such hard X-ray signals, inverse…

High Energy Astrophysical Phenomena · Physics 2018-01-17 M. G. Baring , Z. Wadiasingh , P. L. Gonthier , A. K. Harding

We present a spectroscopic study of 41 hard X-ray sources detected serendipitously with high significance (> 5 sigma in the 2-10 keV band) in seven EPIC performance/verification phase observations. The large collecting area of EPIC allows…

Astrophysics · Physics 2009-11-07 E. Piconcelli , M. Cappi , L. Bassani , F. Fiore , G. DiCocco , J. B. Stephen

In the magnetar model, the quiescent non-thermal soft X-ray emission from Anomalous X-ray Pulsars and Soft-Gamma Repeaters is thought to arise from resonant comptonization of thermal photons by charges moving in a twisted magnetosphere.…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Rodrigo Fernández , Shane W. Davis

We have surveyed 188 ROSAT PSPC fields for X-ray sources with hard spectra (alpha<0.5); such sources must be major contributors to the X-ray background at faint fluxes. In this paper we present optical identifications for 62 of these…

Astrophysics · Physics 2009-11-06 M. J. Page , J. P. D. Mittaz , F. J. Carrera

A synthesis model for the cosmic X-ray Background (XRB) is presented, which includes a proper treatment of Compton scattering in the absorbing matter for type 2 AGN. Evidence for a decrease of the relative importance of type 2 AGN at high…

Astrophysics · Physics 2007-05-23 Giorgio Matt , Fulvio Pompilio , Fabio La Franca

The notable absence of radio pulsars having measured magnetic dipole surface field strengths above $B_0\sim 3\times 10^{13}$ Gauss naturally raises the question of whether this forms an upper limit to pulsar magnetization. Recently there…

Astrophysics · Physics 2009-10-30 Matthew G. Baring , Alice K. Harding

We present photometry of the Anomalous X-ray pulsar 1E1048.1-5937 in the infrared and optical, taken at Magellan and the VLT. The object is detected in the I, J and Ks bands under excellent conditions. We find that the source has varied…

Astrophysics · Physics 2009-11-10 Martin Durant , Marten H. van Kerkwijk

The recent discovery of the "weak field, old magnetar", the soft gamma repeater SGR 0418+5729, whose dipole magnetic field is less than 7.5 \times 10^{12} G, has raised perplexing questions: How can the neutron star produce SGR-like bursts…

High Energy Astrophysical Phenomena · Physics 2015-05-30 S. Dall'Osso , J. Granot , T. Piran

We present a model for the anomalous X-ray pulsars (AXPs) in which the emission is powered by accretion from a fossil disk, established from matter falling back onto the neutron star following its birth. The time-dependent accretion drives…

Astrophysics · Physics 2009-10-31 Pinaki Chatterjee , Lars Hernquist , Ramesh Narayan

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

We propose a model to account for the bursts from soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) in which quantum electrodynamics (QED) plays a vital role. In our theory, that we term ``fast-mode breakdown,''…

Astrophysics · Physics 2014-10-13 Jeremy S. Heyl , Lars Hernquist

The detection of gamma-ray emission from accreting pulsars in X-ray binaries (XRBs) has long been sought after. For some high-mass X-ray binaries (HMXBs), marginal detections have recently been reported. Regardless of whether these will be…

High Energy Astrophysical Phenomena · Physics 2023-08-14 L. Ducci , P. Romano , S. Vercellone , A. Santangelo

There is a general consensus about the fact that the magnetar scenario provides a convincing explanation for several of the observed properties of the Anomalous X-ray Pulsars and the Soft Gamma Repeaters. However, the origin of the emission…

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

The rapid variability of X-ray binaries produces a wide range of X-ray states that are linked to activity across the electromagnetic spectrum. It is particularly challenging to study a sample of sources large enough to include all types in…

High Energy Astrophysical Phenomena · Physics 2023-06-30 John M. Dickey , S. D. Vrtilek , Michael McCollough , Bram Boroson , John A. Tomsick , Charles Bailyn , Jay M. Blanchard , Charlotte Johnson

We examined the fall-back disk models, and in general accretion, proposed to explain the properties of anomalous X-ray pulsars (AXPs), soft gamma repeaters (SGRs), and radio pulsars (PSRs). We checked the possibility of some gas remaining…

Astrophysics · Physics 2009-11-07 S. O. Tagieva , E. Yazgan , A. Ankay

In January 2009, the 2.1-sec anomalous X-ray pulsar 1E 1547.0-5408 evoked intense burst activity. A follow-up Suzaku observation on January 28 recorded enhanced persistent emission both in soft and hard X-rays (Enoto et al. 2010b). Through…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Teruaki Enoto , Yujin E. Nakagawa , Takanori Sakamoto , Kazuo Makishima

Among hard X-ray Galactic sources detected in the Swift and INTEGRAL surveys, those discovered as accreting white dwarf binaries have suprisingly boosted in number in the recent years. The majority are identified as magnetic Cataclysmic…

High Energy Astrophysical Phenomena · Physics 2020-01-24 D. de Martino , F. Bernardini , K. Mukai , M. Falanga , N. Masetti

We show that the irradiated accretion disk model can account for all the optical and infrared observations of the anomalous X-ray pulsars in the persistent state. Model fits do not constrain the outer disk radii, while placing an upper…

Astrophysics · Physics 2015-06-24 Unal Ertan , Sirin Caliskan

We investigate accelerated electron energy spectra for different sources in a large flare using simultaneous observations obtained with two instruments, the Nobeyama Radio Heliograph (NoRH) at 17 and 34 GHz, and the Reuven Ramaty High…

Solar and Stellar Astrophysics · Physics 2015-05-13 M. R. Kundu , V. V. Grechnev , S. M. White , E. J. Schmahl , N. S. Meshalkina , L. K. Kashapova
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