Related papers: Low Frequency Radio Observations of GRS1915+105 wi…
We report the GMRT observations of V4641 Sgr during the May 2002 outburst at radio frequencies of 610 and 244 MHz. This is the lowest frequency radio detection of this source. The present low frequency radio observations clearly showed…
We have observed microquasar GRS 1915+105 at 1.28 GHz for 8 days from June 18 to July 1, 2001 using Giant Metrewave Radio Telescope (GMRT). We have seen several isolated radio baby flares of varying intensity and duration. We have also…
We present the first detections of the black hole X-ray binary GRS 1915+105 at sub-millimetre wavelengths. We clearly detect the source at 350 GHz on two epochs, with significant variability over the 24 hr between epochs. Quasi-simultaneous…
We have observed the micro-quasar V4641 Sgr (SAX J1819.3-2525) at the time of flare during May 2002, using the Giant Metrewave Radio Telescope at low radio frequencies (244 and 610 MHz). This is the lowest frequency radio detection of the…
We report on the timing analysis of RXTE observations of the Galactic micro-quasar GRS 1915+105 performed in 2003. Out of a total of six times ~20 ks, we focus here only on the three observations during which GRS 1915+105 is found in a…
The two galactic `microquasars' with superluminal radio jets have been quite active during 1996, generatinga variety of studies involving both NASA and ground-based observatories. GRS~1915+105 has displayed dramatic accretion instability in…
GRS 1915+105 is a very well studied microquasar with a wide variety of temporal and spectral states. Multi-wavelength observations from radio to X-rays have uncovered clear relations between the variability in different bands. GRS 1915+105…
The large mechanical luminosity of the jets of GRS 1915+105 should give rise to luminous emission regions, similar to those observed in radio galaxies, where the jets interact with the gas surrounding the source. However, no radio…
We report radio imaging and monitoring observations in the frequency range 0.235 - 2.7 GHz during the flaring mode of PKS 2155-304, one of the brightest BL Lac objects. The high sensitivity GMRT observations not only reveal extended…
Microquasars are compact binary systems hosting collimated relativistic jets. They have long been proposed as cosmic-ray accelerators, probed via the gamma-ray emission produced by relativistic particles. However, the observational evidence…
We present the result of multi-wavelength observations of the microquasar GRS 1915+105 in a plateau state with a luminosity of ~7.5x10^{38) erg s-1 (~40% L_Edd), conducted simultaneously with the INTEGRAL and RXTE satellites, the ESO/NTT,…
We observed the galactic microquasar GRS1915+105 in the K ($2.2 \mu$m) band on October 16 and 17, 1995 UTC using the COB infrared (IR) imager on the Kitt Peak National Observatory 2.1-m telescope with a 0.2-arcsec/pixel plate scale and…
Using the Alternative Data Release of the TIFR GMRT Sky Survey (TGSS), we studied the low-frequency properties of FR0 radio galaxies, the large population of compact radio sources associated with red massive early-type galaxies revealed by…
We discuss the results of the radio studies of the X-ray binaries with relativistic jets. We carried out a multi-frequency (1-30 GHz) daily monitoring of the radio flux variability of the microquasars SS433, GRS1915+105, and Cyg X-3 with…
The jets of GRS 1915+105 carry a considerable energy away from the central source into the ISM. The similarity of the jets of this source and jets in radio galaxies or radio-loud quasars suggests that we should detect large-scale,…
Powerful relativistic jets are one of the ubiquitous features of accreting black holes in all scales. GRS 1915+105 is a well-known fast-spinning black-hole X-ray binary with a relativistic jet, termed as a ``microquasar'', as indicated by…
Microquasars are X-ray binary systems with non-thermal radio emission originated in jet-like features. They are attractive sites for gamma-ray production, since relativistic particles in the jet should traverse locally strong both photon…
We present a low-frequency imaging study of an extended sample of X-shaped radio sources using the Giant Metrewave radio telescope (GMRT) at two frequencies (610 and 240 MHz). The sources were drawn from a Very Large Array FIRST-selected…
We analyse a set of three RXTE Target of Opportunity observations of the Galactic microquasar GRS 1915+105, observed in April 2000. We concentrate on the timing properties of the source, and examine the properties of a low frequency QPO,…
Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and laboratories for elucidating the physics of relativistic jets. Here we report the detection of variable gamma-ray…