Results 21 to 30 of about 238,966 (146)
Unlocking the nature of ultraluminous X-ray sources using their X-ray spectra [PDF]
, 2011 We explore the nature of ultraluminous X-ray sources through detailed investigations of their spectral shape using some of the highest quality data available in the XMM-Newton public archives. Phenomenological models allow us to characterise their spectra, while more 'physically-motivated' models enable us to explore the physical processes underlying ...
arxiv +1 more source
East European Journal of Physics, 2023 The present work aims to study the previously unstudied Ultraluminous X-ray sources (ULXs) in the galaxy NGC 3585 at its various epochs of Chandra observation. We report here the detection of two new ULXs viz.
S. Rita Devi +2 more
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Yet another galaxy identification for an ultraluminous X-ray source [PDF]
Astron.Astrophys. 406 (2003) L27-L32, 2003 We report on the identification of the optical and infrared counterparts of the ultraluminous X-ray source (ULX) XMMU J121214.5+131248 (NGC4168-ULX1). The optical spectrum yields a redshift of z=0.217, which implies that the ULX is not associated with the nearby galaxy NGC 4168, but rather with a background object.
arxiv +1 more source
NGC 7793 P9: An Ultraluminous X-Ray Source Evolved from a Canonical Black Hole X-Ray Binary [PDF]
, 2018 Transient ultraluminous X-ray sources (ULXs) provide an important link bridging transient low-mass X-ray binaries and ULXs. Here we report the first discovery of both a canonical sub-Eddington outburst and an ultraluminous super-Eddington outburst from an unusual transient ULX, NGC 7793 P9 with a variability factor higher than $10^3$.
arxiv +1 more source
The Astrophysical Journal, 2023 The formation path to ultracompact X-ray binaries (UCXBs) with black hole (BH) accretors is still unclear. In the classical formation scenario, it is difficult to eject the massive envelope of the progenitor star of the BH via the common envelope process.
Hai-Liang Chen +3 more
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Chandra reveals a black-hole X-ray binary within the ultraluminous supernova remnant MF 16 [PDF]
Mon.Not.Roy.Astron.Soc. 341 (2003) L49, 2003 We present evidence, based on Chandra ACIS-S observations of the nearby spiral galaxy NGC 6946, that the extraodinary X-ray luminosity of the MF 16 supernova remnant actually arises in a black-hole X-ray binary. This conclusion is drawn from the point-like nature of the X-ray source, its X-ray spectrum closely resembling the spectrum of other ...
arxiv +1 more source
X-Ray Views of Galactic Accreting Pulsars in High-Mass X-Ray Binaries
UniverseAccreting X-ray pulsars, located in X-ray binaries, are neutron stars with magnetic fields as strong as B∼1012–13 G. This review offers a concise overview of the accretion and radiation processes of X-ray pulsars and summarizes their rich observational ...
Shan-Shan Weng, Long Ji
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The Astrophysical Journal, 2023 We present a detailed compilation and analysis of the X-ray phase space of low- to intermediate-redshift (0 ≤ z ≤ 1) transients that consolidates observed light curves (and theory where necessary) for a large variety of classes of transient/variable ...
Ava Polzin +10 more
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Cutoff in the hard X-ray spectra of the ultraluminous X-ray sources HoIX X-1 and M82 X-1 [PDF]
, 2013 Using data from the XMM-Newton and INTEGRAL observatories, we have detected a cutoff at energies above 10 keV in the X-ray spectra of the ultraluminous X-ray sources HoIX X-1 and M82 X-1. The spectra obtained can be described by a model of Comptonization of radiation in a gas cloud of moderate temperature (kT~2-3 keV) and high optical depth (tau~15-25).
arxiv +1 more source
The Long-term Spin-down Trend of Ultraluminous X-Ray Pulsar M82 X-2
The Astrophysical JournalThe discovery in 2014 of the pulsation from the ultraluminous X-ray source (ULX) M82 X-2 has changed our view of ULXs. Because of the relatively short baseline over which pulsations have been detected so far, M82 X-2's spin state had been assumed to be ...
Jiren Liu
doaj +1 more source