Results 81 to 90 of about 9,171,233 (161)
The Astrophysical JournalWe searched the Chandra and XMM archives for 900 Green Pea galaxies to identify signs of active galactic nuclei (AGN). Green peas are low-mass, emission-line galaxies that resemble high-redshift dwarf galaxies. From 29 observations, we detected X-rays in
Mainak Singha +10 more
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Ultraluminous X‐ray sources: Three exciting years [PDF]
Astronomische Nachrichten, 2016 AbstractThe extreme extragalactic sources known as Ultraluminous X‐ray Sources (ULX) represent a unique testing environment for compact objects population studies and the accretion process. Their nature has long been disputed. Their luminosity, well above the Eddington luminosity for a stellar‐mass black hole, can imply the presence of an intermediate ...
openaire +2 more sources
Discovery of a Candidate 2 keV Cyclotron Resonance Scattering Feature in the HLX NGC 3583 X-1
The Astrophysical JournalWe present a broadband X-ray study of the transient hyperluminous X-ray source (HLX), 2SXPS J111416.1+481833, in the galaxy NGC 3583, using archival XMM-Newton, NuSTAR, and Chandra data, and long-term Swift X-ray Telescope monitoring.
Kiran M. Jayasurya +2 more
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Monitoring of the Spectral and Timing Properties of the Ultraluminous X-Ray Pulsar NGC 7793 P13
The Astrophysical Journal LettersWe present the long-term spectral and timing evolution of the ultraluminous X-ray pulsar NGC 7793 P13 from 2011 to 2024 based on archival data from XMM-Newton, Chandra, NICER, and NuSTAR, including unpublished data after 2020. This data set enables us to
Marina Yoshimoto +5 more
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Ultraluminous X-ray Sources in M51
, 2002 4 pages, to appear in the Proceedings of the Symposium on ``New Visions of the Universe in the XMM-Newton and Chandra Era'', 26-30 November 2001, ESTEC, The ...
Terashima, Yuichi, Wilson, Andrew S.
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The Astrophysical JournalUltraluminous X-ray sources (ULXs) were once largely believed to be powered by super-Eddington accretion onto stellar-mass black holes, although in some rare cases, ULXs also serve as potential candidates for (sub-Eddington) intermediate-mass black holes.
Teresa Panurach +10 more
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A Fallback Disk Model for Ultraluminous X-Ray Sources [PDF]
The Astrophysical Journal, 2003 Current stellar evolution models predict that during the core collapse of massive stars, a considerable amount of the stellar material will fall back onto the compact, collapsed remnants (neutron stars or black holes), usually in the form of an accretion disk.
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The Astrophysical JournalTo investigate the population of massive black holes in dwarf galaxies, we conduct a systematic search for active galactic nuclei (AGNs) using data from the first data release of the eROSITA All-Sky Survey (eRASS). We crossmatch dwarf galaxy positions in
John-Michael Eberhard, Amy E. Reines
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Accretion rates and beaming in ultraluminous X-ray sources [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2008 Abstract I show that extreme beaming factors b are not needed to explain ultraluminous X-ray sources (ULXs) as stellar-mass binaries. For neutron-star accretors, one typically requires b∼ 0.13, and for black holes almost no beaming (b∼ 0.8).
openaire +3 more sources
The properties of discrete X-ray sources in star-forming galaxies [PDF]
, 2012 Observations of starburst galaxies have revealed a large number of point-like X-ray sources located within these systems, including active galactic nuclei (AGN), X-ray binaries (XRBs), and utraluminous X-ray sources (ULXs).
JACKSON, FLOYD,EMMANUEL
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