Results 71 to 80 of about 195 (150)
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 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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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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The Astrophysical JournalX-ray quasiperiodic oscillations (QPOs) are commonly observed in Galactic X-ray binaries and extragalactic ultraluminous X-ray sources (ULXs). In this study, we perform a phase-resolved analysis of recently discovered X-ray mHz QPOs in M51 ULX-7.
Qing-Cang Shui +5 more
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A candidate proton cyclotron feature in the ultraluminous X-ray source NGC 4656 ULX-1
Astronomy & AstrophysicsUltraluminous X-ray sources represent extreme super-Eddington accretion regimes, and a subset is now known to host highly magnetized neutron stars. However, direct observational probes of their surface magnetic fields remain scarce.
Cruz-Sanchez Nelson +8 more
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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).
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ULX Collimation by Outflows in Moderately Magnetized Neutron Stars
The Astrophysical JournalWe perform radiative magnetohydrodynamics simulations in general relativity of super-Eddington disk accretion onto neutron stars endowed with a magnetic dipole corresponding to surface strengths not exceeding 100 Giga-Gauss.
Fatemeh Kayanikhoo +2 more
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Modelling quantum aspects of disruption of a white dwarf star by a black hole. [PDF]
Sci Rep, 2021 Karpiuk T +3 more
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A NuSTAR Study of Quasiperiodic Oscillations from the Ultraluminous X-Ray Sources in M82
The Astrophysical JournalThe study of quasiperiodic oscillations (QPOs) in X-ray binaries provides valuable insights into the physics of accretion around compact objects. The M82 galaxy hosts multiple ultraluminous X-ray sources, including two prominent ones—X-1 and X-2—where X ...
Hamza El Byad +15 more
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Extragalactic Science with the Orbiting Astronomical Satellite Investigating Stellar Systems (OASIS) Observatory. [PDF]
Space Sci Rev, 2023 Aalto S +7 more
europepmc +1 more source