Results 51 to 60 of about 1,327,251 (363)
Synchrotron Cutoff in Ultraluminous X-Ray Sources
The Astrophysical Journal, 2023 The origin of spectral curvature at energies E ≃ 10 keV in ultraluminous X-ray sources (ULXs) is not well understood. In this paper, we propose a novel mechanism based on synchrotron radiation to explain this cutoff.
Tanuman Ghosh, Shiv Sethi, Vikram Rana
doaj +1 more source
Reionization by UV or X-ray sources [PDF]
Astronomy & Astrophysics, 2010 We present simulations of the 21-cm signal during the epoch of reionization. We focus on properly modeling the absorption regime in the presence of inhomogeneous Wouthuysen-Field effect and X-ray heating. We ran radiative transfer simulations for three bands in the source spectrum (Lyman, UV, and X-ray) to fully account for these processes.
Baek, Sunghye +4 more
openaire +5 more sources
X-ray source population study of the starburst galaxy M83 with XMM-Newton [PDF]
, 2013 We present the results obtained from the analysis of three XMM-Newton observations of M83. The aims of the paper are studying the X-ray source populations in M83 and calculating the X-ray luminosity functions of X-ray binaries for different regions of the galaxy. We detected 189 sources in the XMM-Newton field of view in the energy range of 0.2-12 keV.
arxiv +1 more source
X-ray reflection in a sample of X-ray bright Ultraluminous X-ray sources
, 2009 We apply a reflection-based model to the best available XMM-Newton spectra of X-ray bright UltraLuminous X-ray (ULX) sources (NGC 1313 X-1, NGC 1313 X-2, M 81 X-6, Holmberg IX X-1, NGC 5408 X-1 and Holmberg II X-1).
A. C. Fabian +52 more
core +1 more source
Supersoft X-Ray Sources in M31 [PDF]
, 1996 The nearby Andromeda galaxy (M31) has been observed with the ROSAT PSPC in a mosaic of 6 pointings with 25 ksec each. In the paper describing the results on the total sample of detected sources, Supper et al.
D. Grupe +10 more
core +2 more sources
Ultraluminous X-ray sources are beamed
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT We show that magnetar models for ultraluminous X-ray sources (ULXs) have serious internal inconsistencies. The magnetic fields required to increase the limiting luminosity for radiation pressure above the observed (assumed isotropic) luminosities are completely incompatible with the spin-up rates observed for pulsing ULXs.
Jean–Pierre Lasota, Andrew King
openaire +5 more sources
DISCRETE X-RAY SOURCES IN GALAXY CLUSTERS
Odessa Astronomical Publications, 2020 Current studies of extragalactic X-ray sources using data from orbital observatory XMM- Newton are at the front line of X-ray astronomy. Resolution capacity of the observatory instruments enable to detect separate X-ray sources in the close galaxies.
A. V. Tugay +2 more
doaj +1 more source
Hydrogen-triggered X-Ray Bursts from SAX J1808.4−3658? The Onset of Nuclear Burning
The Astrophysical Journal, 2023 We present a study of weak, thermonuclear X-ray bursts from the accreting millisecond X-ray pulsar SAX J1808.4−3658. We focus on a burst observed with the Neutron Star Interior Composition Explorer on 2019 August 9, and describe a similar burst observed ...
Sierra Casten +2 more
doaj +1 more source
An Ultradeep High Resolution X-ray Image of M101: The X-ray Source Population in a Late-type Spiral [PDF]
, 1999 We have studied the X-ray source population of the face-on spiral galaxy M101 (NGC 5457). Within a field of radius 17' (36 kpc at the distance of 7.2 Mpc), covered by an ultradeep (229 ks) ROSAT HRI image, 51 X-ray sources are detected with signal-to-noise ratios greater than 3.5. About half of these sources are associated with the galaxy. We determine
arxiv +1 more source
The Astrophysical Journal, 2023 Gamma-ray binary systems, a subclass of high-mass X-ray binaries, show nonthermal emissions from radio to TeV. While efficient electron acceleration is considered to take place in them, the nature of the acceleration mechanism and the physical ...
Hiroki Yoneda +7 more
doaj +1 more source