Related papers: Evolution of Intermediate-Mass Black Hole X-Ray Bi…
This chapter discusses the implications of X-ray binaries on our knowledge of Type Ibc and Type II supernovae. X-ray binaries contain accreting neutron stars and stellar--mass black holes which are the end points of massive star evolution.…
We review observations of ultraluminous X-ray sources (ULXs). X-ray spectroscopic and timing studies of ULXs suggest a new accretion state distinct from those seen in Galactic stellar-mass black hole binaries. The detection of coherent…
Many upcoming surveys, particularly in the radio and optical domains, are designed to probe either the temporal and/or the spatial variability of a range of astronomical objects. In the light of these high resolution surveys, we review the…
We study the origin of the ultraluminous X-ray source M82-X1 in the nearby starburst galaxy M82. This X-ray source is of particular interest as it is currently the best candidate intermediate mass black hole; it is associated with a 54mHz…
We study the formation of low-mass X-ray binaries with a black hole as accreting object. The performed semi-analytic analysis reveals that the formation rate of black holes in low-mass X-ray binaries is about two orders of magnitude smaller…
We examine the possibility that Ultraluminous X-ray sources (ULXs) represent the extreme end of the black hole X-ray binary (XRB) population. Based on their X-ray properties, we suggest that ULXs are persistently in a high/hard spectral…
Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities $\geq$ 10$^{39}$ erg s$^{-1}$. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate…
Gravitational waves from the binary black hole (BH) merger GW150914 may enlighten our understanding of ultra-luminous X-ray sources (ULXs), as BHs>30Msun can reach luminosities>4x10^39 erg s^-1 without exceeding their Eddington limit. It is…
X-ray binaries with black hole (BH) accretors and massive star donors at short orbital periods of a few days can evolve into close binary BH systems (BBH) that merge within the Hubble time through stable mass transfer evolution. From…
Ultraluminous X-ray sources (ULXs) are likely to include different physical types of objects. We discuss some possible subclasses, reviewing the properties of a sample of ULXs recently observed by Chandra and XMM-Newton. Sources with an…
Ultraluminous X-ray binaries have challenged our assumptions of extreme accretion rates in X-ray binaries, and impact other subfields of astronomy, such as cosmology, gravitational wave sources and supernov{\ae}. Our understanding of ULXs…
We consider observational tests for the nature of Ultraluminous X-ray sources (ULXs). These must distinguish between thermal-timescale mass transfer on to stellar-mass black holes leading to anisotropic X-ray emission, and accretion on to…
We calculate the formation rates of low-mass X-ray binaries with a black hole. Both a semi-analytic and a more detailed model predict formation rates two orders of magnitude lower than derived from the observations. Solution of this…
In this proof-of-concept study we demonstrate that in a binary system mass can be transferred toward an accreting compact object at extremely high rate. If the transferred mass is efficiently converted to X-ray luminosity (with disregard of…
Observations of high-redshift quasars frequently promote suggestions of large black hole masses, whose presence so early in cosmic time is not easily explicable. I consider the parallel with ultraluminous X-ray sources (ULXs) -- now known…
The nature of ultraluminous X-ray sources (ULXs) is still debated. Recent studies show that metal-poor massive stars can collapse into massive stellar black holes (MSBHs), that is black holes with mass > 25 Msun. Such MSBHs are sufficiently…
Ultra-luminous X-ray sources (ULXs) are the most extreme members of the X-ray binary population, exhibiting X-ray luminosities that can surpass the 10^39 erg/s threshold (by orders of magnitude). They are mainly seen in external galaxies…
A large fraction of X-ray sources in our Galaxy are low-mass X-ray binaries, containing a black hole or a neutron star accreting from a gravitationally bound low-mass ($\leq$1 M$_\odot$) companion star. These systems are among the older…
The 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,…
We review the available estimates of the masses of the compact object in Ultraluminous X-ray Sources (ULXs) and critically reconsider the stellar-mass versus intermediate-mass black hole interpretations. Black holes of several hundreds to…