Results 11 to 20 of about 33,018 (264)
Survey of X-ray pulsars in hard X-rays [PDF]
Proceedings of The Extreme sky: Sampling the Universe above 10 keV — PoS(extremesky2009), 2010 Results of spectral, timing and spatial analysis of X-ray pulsars in hard X-rays are briefly discussed. Using data of INTEGRAL, XMM-Newton and Chandra observatories we determined an optical counterparts and distances for several X-ray pulsars and built the spatial distribution of this class objects in the Galaxy. Variations of the cyclotron line energy
Alexander Lutovinov, Sergey Tsygankov
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An X‐Ray Survey of Galaxies in Pairs [PDF]
The Astrophysical Journal, 1999 Results are reported from the first survey of X-ray emission from galaxies in pairs. The sample consists of fifty-two pairs of galaxies from the Catalog of Paired Galaxies Karachentsev (1972) whose coordinates overlap ROSAT Position Sensitive Proportional Counter pointed observations.
Henriksen, M., Cousineau, S.
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Revisiting X-Ray-bright Optically Normal Galaxies with the Chandra Source Catalog
The Astrophysical Journal, 2023 X-ray bright optically normal galaxies (XBONGs) are galaxies with X-ray luminosities consistent with those of active galactic nuclei (AGNs) but no evidence of AGN optical emission lines.
Dong-Woo Kim +5 more
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In-orbit Background and Sky Survey Simulation Study of POLAR-2/LPD
The Astrophysical Journal, 2023 The Low-Energy X-ray Polarization Detector (LPD) is one of the payloads in the POLAR-2 experiment, designed as an external payload for the China Space Station deployment in early 2026. LPD is specifically designed to observe the polarization of gamma-ray
Zu-Ke Feng +16 more
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The Soft X-ray Excess in Quasars and Deep X-ray Surveys [PDF]
Symposium - International Astronomical Union, 1994 We examine the surface density of quasars expected in the ROSAT PSPC surveys, using quasar optical luminosity functions and model continuum spectra including a soft X-ray excess. We show that the surface density is a sensitive function of the characteristic energy of the soft excess, and the absorption within the quasar as well as the interstellar ...
Ajit Kembhavi, A. C. Fabian
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Target Detection Framework for Lobster Eye X-Ray Telescopes with Machine-learning Algorithms
The Astrophysical Journal Supplement Series, 2023 Lobster eye telescopes are ideal monitors to detect X-ray transients because they could observe celestial objects over a wide field of view in the X-ray band.
Peng Jia, Wenbo Liu, Yuan Liu, Haiwu Pan
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BASS. XXVI. DR2 Host Galaxy Stellar Velocity Dispersions
The Astrophysical Journal Supplement Series, 2022 We present new central stellar velocity dispersions for 484 Sy 1.9 and Sy 2 from the second data release of the Swift/BAT AGN Spectroscopic Survey (BASS DR2).
Michael J. Koss +20 more
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A High Fraction of Heavily X-Ray-obscured Active Galactic Nuclei
The Astrophysical Journal, 2023 We present new estimates on the fraction of heavily X-ray-obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift of z ≤ 0.8. From a sample of 540 AGNs selected by mid-infrared (MIR) properties in observed X-ray survey fields, we ...
Christopher M. Carroll +7 more
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The Astrophysical Journal, 2023 Dwarf galaxies are promising test beds for constraining models of supermassive and intermediate-mass black holes (MBHs) via their BH occupation fraction (BHOF).
Urmila Chadayammuri +3 more
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BASS. XXI. The Data Release 2 Overview
The Astrophysical Journal Supplement Series, 2022 The BAT AGN Spectroscopic Survey (BASS) is designed to provide a highly complete census of the key physical parameters of the supermassive black holes (SMBHs) that power local active galactic nuclei (AGNs) ( z ≲ 0.3), including their bolometric ...
Michael J. Koss +26 more
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