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X-Ray Spectroscopic Evidence for Intermediate-Mass Black Holes: Cool Accretion Disks in Two Ultraluminous X-Ray Sources
We have analyzed an XMM-Newton observation of the nearby spiral galaxy NGC 1313, which contains two ultraluminous X-ray (ULX) sources. We measure isotropic luminosities of LX = 2.0 × 1040 ergs s-1Expand
Production of intermediate-mass black holes in globular clusters
The discovery of numerous non-nuclear X-ray point sources with luminosities L>1039 erg s−1 in several starburst galaxies has stimulated speculation about their nature and origin. The strongExpand
Sonic-Point Model of Kilohertz Quasi-periodic Brightness Oscillations in Low-Mass X-Ray Binaries
Quasi-periodic brightness oscillations (QPOs) with frequencies ranging from ~300 to ~1200 Hz have been discovered in the X-ray emission from 14 neutron stars in low-mass binary systems and fromExpand
PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
Neutron stars are not only of astrophysical interest, but are also of great interest to nuclear physicists because their attributes can be used to determine the properties of the dense matter inExpand
Revealing a cool accretion disk in the ultraluminous X-ray source M81 X-9 (Holmberg IX X-1): Evidence for an intermediate-mass black hole
We report the results of an analysis of two XMM-Newton EPIC-pn spectra of the bright ultraluminous X-ray source M81 X-9 (Holmberg IX X-1) obtained in snapshot observations. Soft thermal emission isExpand
Measuring the spin of GRS 1915+105 with relativistic disk reflection
GRS 1915+105 harbors one of the most massive known stellar black holes in the Galaxy. In 2007 May, we observed GRS 1915+105 for ∼117 ks in the low/hard state using Suzaku. We collected and analyzedExpand
Modeling Kicks from the Merger of Generic Black Hole Binaries
ABSTRACT Recent numerical relativistic results demonstrate that the merger of comparable-mass spinning black holes has a maximum "recoil kick" of up to N 4000 km s-l. However the scaling of theseExpand
A number of neutron star low-mass X-ray binaries (LMXBs) have recently been discovered to show broad, asymmetric Fe K emission lines in their X-ray spectra. These lines are generally thought to beExpand
An abrupt drop in the coherence of the lower kHz quasi-periodic oscillations in 4U 1636-536
Using archival data from the Rossi X-ray Timing Explorer (RXTE), we study in a systematic way the variation of the quality factor (Q = ν/�ν , �ν , full width at half maximum) and amplitude of theExpand
Flows of X-ray gas reveal the disruption of a star by a massive black hole
Flows of hot, ionized gas are detected in high-resolution X-ray spectra of a nearby tidal disruption event, ASASSN-14li in the galaxy PGC 043234, consistent with a rotating wind from the inner, super-Eddington region of a nascent accretion disk, or with a filament of disrupted stellar gas near to the apocentre of an elliptical orbit. Expand