Related papers: SS433:the microquasar link with ULXs?
Using the unique X-ray imaging capabilities of the Chandra observatory, a 2006 observation of Cygnus X-3 has provided insight into a singular feature associated with this well-known microquasar. This extended emission, located ~16…
How black holes are formed remains an open and fundamental question in Astrophysics. Despite theoretical predictions, it lacks observations to understand whether the black hole formation experiences a supernova explosion. Here we report the…
We investigate the evolution of the properties of model populations of ultraluminous X-ray sources (ULXs) consisting of a black-hole accretor in a binary with a donor star. We have computed models corresponding to three different…
X-ray binaries are composed of a normal star in orbit around a neutron star or stellar-mass black hole. Radio and X-ray observations have led to the presumption that some X-ray binaries called microquasars behave as scaled down active…
The microquasar SS 433 is well-known for its precessing, relativistic baryonic jets. Depending on their heating mechanism, the optical jet bullets may serve as a probe of the collimated radiation coming from the inner region close to the…
We consider ultraluminous X-ray sources (ULXs) where the accretor is a neutron star rather than a black hole. We show that the recently-discovered example (M82 X-2) fits naturally into the simple picture of ULXs as beamed X-ray sources fed…
We present new multi-wavelength observations of two ultraluminous X-ray sources (ULXs) hosted by globular clusters (GCs) in the giant elliptical NGC 1399, focusing on CXO J0338318-352604 (GCU7), only the second GC ULX known to have luminous…
LS I +61 303 is a puzzling object detected from radio up to high-energy gamma-rays. Variability has recently been observed in its high-energy emission. The object is a binary system, with a compact object and a Be star as primary. The…
We present observations of the SS 433 jets using the Chandra High Energy Transmission Grating Spectrometer with contemporaneous optical and VLBA observations. The X-ray and optical emission line regions are found to be related but not…
The emission of $\gamma$-rays in jets emanating from the vicinity of collapsed stellar remnants, in binary systems known as microquasars, is investigated using a three dimensional relativistic hydrocode (PLUTO), in combination with two…
Cygnus X-3 is a unique microquasar. Its X-ray emission shows a very strong 4.8-hour orbital modulation. But its mass-donating companion is a Wolf-Rayet star. Also unlike most other X-ray binaries Cygnus X-3 is relatively bright in the radio…
Microquasars are compact objects (stellar-mass black holes and neutron stars) that mimic, on a smaller scale, many of the phenomena seen in quasars. Their discovery provided new insights into the physics of relativistic jets observed…
We present discovery of a radio nebula associated with the ultraluminous X-ray source (ULX) IC 342 X-1 using the Very Large Array (VLA). Taking the surrounding nebula as a calorimeter, one can constrain the intrinsic power of the ULX…
Ultraluminous X-ray Sources (ULXs) in globular clusters are low mass X-ray binaries that achieve high X-ray luminosities through a currently uncertain accretion mechanism. Using archival Chandra and Hubble Space Telescope observations, we…
Ultraluminous X-ray sources (ULXs) with 10^39 < L_x < 10^41 erg/s have been discovered in great numbers in external galaxies with ROSAT, Chandra, and XMM-Newton. The central question regarding this important class of sources is whether they…
The black hole mass and accretion rate in Ultraluminous X-ray sources (ULXs) in external galaxies, whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times$^{1,2}$, is an unsolved…
SS433 is a Galactic microquasar with powerful outflows (double jet, accretion disk and winds) with well known orbital, precessional and nutational period. In this work we characterise different outflow parameters throughout the precessional…
The origin of Ultraluminous X-ray Sources (ULXs) in external galaxies whose X-ray luminosities exceed those of the brightest black holes in our Galaxy by hundreds and thousands of times is mysterious. The most popular models for the ULXs…
With their relatively fast variability time-scales, Galactic X-ray binaries provide an excellent laboratory to explore the physics of accretion and related phenomena, most notably outflows, over different regimes. After comparing the…
Microquasars are stellar-mass black holes accreting matter from a companion star and ejecting plasma jets at almost the speed of light. They are analogues of quasars that contain supermassive black holes of $10^6$ to $10^{10}$ solar masses.…