Related papers: Understanding Cygnus X-3 Through Multi-Wavelength …
We briefly review the Galactic microquasar SS 433/W50 and present a new RXTE spectral and timing study. We show that the X-ray flux decreases during radio flares, a behavior seen in other microquasars. We also find short time-scale…
The microquasar SS 433 is an interacting massive binary consisting of an evolved mass donor and a compact companion that ejects relativistic jets. The mass donor was previously identified through spectroscopic observations of absorption…
We have investigated the long term flux variation in Cen X-3 using orbital modulation and pulsed fraction in different flux states using observations made with the All Sky Monitor and the Proportional Counter Array on board the Rossi X-ray…
We present near-simultaneous Chandra/HST observations of the very faint ($L_{x} < 10^{36}$ erg s$^{-1}$) X-ray transient source M15 X-3, as well as unpublished archival Chandra observations of M15 X-3. The Chandra observations constrain the…
Accreting black holes are thought to emit the bulk of their power in the X-ray band by releasing the gravitational potential energy of the infalling matter. At the same time, they are capable of producing highly collimated jets of energy…
We report the results of an observation of Cygnus X-1 with INTEGRAL, that we combine with simultaneous radio observations with the Ryle telescope. Both spectral and variability properties of the source indicate that Cygnus X-1 was in an…
Multifrequency observations from the VLA, VLBA and OVRO Millimeter Array of a major radio outburst of Cygnus X-3 in 2001 September are presented, measuring the evolution of the spectrum of the source over three decades in frequency, over a…
The properties of the orbit and the donor star in the high mass X-ray binary microquasar LS 5039 indicate that accretion processes should mainly occur via a radiatively driven wind. In such a scenario, significant X-ray variability would be…
LSI +61 303 is one of the few X-ray binaries with Be star companion from which both radio and high-energy gamma-ray emission have been observed. We present XMM-Newton and INTEGRAL observations which reveal variability of the X-ray spectral…
Context. Supergiant fast X-ray transients are a subclass of high mass X-ray binaries that host a neutron star accreting mass from the wind of its OB supergiant companion. They are characterized by an extremely pronounced and rapid…
The small mission A-STAR (All-Sky Transient Astrophysics Reporter) aims to locate the X-ray counterparts to ALIGO and other gravitational wave detector sources, to study the poorly-understood low luminosity gamma-ray bursts, and to find a…
Results are presented from recent VLBI observations of Cygnus X-1 during X-ray spectral state changes. Using the EVN in e-VLBI mode and the VLBA with disk recording, we observed the X-ray binary at very high angular resolution and studied…
To gain a better understanding of high-energy Galactic sources, we observed the Galactic X-ray binary and black hole candidate XTE J1720-318 in the optical and near-infrared, just after the onset of its X-ray outburst in January, 2003.…
Microquasars are stellar x-ray binaries that behave as a scaled down version of extragalactic quasars. The star LS 5039 is a new microquasar system with apparent persistent ejection of relativistic plasma at a 3 kiloparsec distance from the…
We have observed a number of minor radio flares in Cyg X-3 using the MERLIN array. Photometric observations show the system to be highly active with multiple flares on hourly timescales over the one month observing programme. Analysis of…
We present the results of multi-year gamma-ray observations by the AGILE satellite of the black hole binary system Cygnus X-1. In a previous investigation we focused on gamma-ray observations of Cygnus X-1 in the hard state during the…
Ultracompact X-ray binaries (UCXBs) have orbital periods shorter than about 80 minutes and typically consist of a neutron star that accretes hydrogen-poor matter from a white dwarf companion. Angular momentum loss via gravitational wave…
Observations with the Newton X-ray Multimirror Mission (XMM) show a strong periodic modulation at 6.67+/-0.03 hours of the X-ray source at the centre of the 2,000-year-old supernova remnant RCW 103. No fast pulsations are visible. If…
The long-term transitions of the black hole candidate Cygnus X-1 (between the states gamma_1, gamma_2, and gamma_3) include the occasional appearance of a strong ~ MeV bump (gamma_1), whose strength appears to be anti-correlated with the…
EZ Canis Majoris is a classical Wolf-Rayet star whose binary nature has been debated for decades. It was recently modeled as an eccentric binary with a periodic brightening at periastron of the emission originating in a shock heated zone…