Related papers: On the distance of GRO J1655-40
We review some specific and quantitative issues in popular methods used to determine the distance of galactic objects, in the context of the microquasars GRO J1655-40 and 1A 0620-00. In particular, we discuss the domain of validity of the…
GRO J1655--40 is a galactic microquasar, i.e. a short-period binary with relativistic radio-jets and where the companion is a black-hole. A little after its discovery in 1994 by $BATSE$, a distance of 3.2$\pm$0.2 kpc has been estimated, and…
We examine the distance of the two galactic microquasars GRO J1655-40 and A0620-00, which are potentially the two closest black holes to the Sun. We aim to provide a picture as wide and complete as possible of the problem of measuring the…
The X-ray/radio transient superluminal jet source GRO J1655-40 was recently suggested to contain a black hole from optical observations. Being a relatively close-by system (d \sim 3.2 kpc), it can likely provide us with rich information…
We report on several European Southern Observatory (ESO) near-infrared (NIR) observational campaigns aimed at understanding the nature of galactic black hole candidates. Our results, including NIR photometry of the sources GRO J1655-40, GRS…
Aims. Motivated by the new determination of the distance to the microquasar GRO J1655-40 by Foellmi et al. (2006), we conduct a detailed study of the distribution of the atomic and molecular gas, and dust around the open cluster NGC 6242,…
We present broad-band (2 keV to 2 MeV) X-ray spectra of GRO J1655-40, a luminous X-ray transient and occasional source of relativistic radio jets, obtained with RXTE and OSSE. In one observation, the luminosity is found to be 18% of the…
We present ellipsoidal light-curve fits to the quiescent B, V, R and I light curves of GRO J1655-40 (Nova Scorpii 1994). The fits are based on a simple model consisting of a Roche-lobe filling secondary and an accretion disc around the…
The Galactic black-hole binary GRO J1655$-$40 was observed with Suzaku on 2005 September 22--23, for a net exposure of 35 ks with the X-ray Imaging Spectrometer (XIS) and 20 ks with the Hard X-ray Detector (HXD). The source was detected…
We report optical spectroscopic observations of the Low Mass X-ray Binary GRO J1655-40 during outbursts in August-September 1994 and in June 1996. The spectra show emission and absorption lines from the accretion disk surrounding the X-ray…
We report photometric and spectroscopic observations of the black hole binary GRO J1655-40 in complete quiescence. In contrast to the 1995 photometry, the light curves from 1996 are almost completely dominated by ellipsoidal modulations…
We have used the Hubble Space Telescope to measure the motion in the sky and compute the galactocentric orbit of the black hole X-ray binary GRO J1655-40. The system moves with a runaway space velocity of $112\pm 18$ km s$^{-1}$ in a highly…
Context: The detection of overabundances of $\alpha$-elements and lithium in the secondary star of a black-hole binary provides important insights about the formation of a stellar-mass black-hole. $\alpha$-enhancement might theoretically…
We present new results from a multi-wavelength (radio/infrared/optical/X-ray) study of the black hole X-ray binary GRO J1655-40 during its 2005 outburst. We detected, for the first time, mid-infrared emission at 24 um from the compact jet…
We report on XMM-Newton observations of GRO J1655-40 and GRS 1009-45, which are two black hole X-ray transients currently in their quiescent phase. GRO J1655-40 was detected with a 0.5 - 10 keV luminosity of 5.9 10^{31} erg/s. This…
We report the discovery of emission features in the X-ray spectrum of GRO J1655-40 obtained with RXTE during the observation of 1997, Feb 26. We have fitted the features firstly by two Gaussian lines which in four spectra analysed have…
We have examined fifteen days of CGRO/BATSE data, obtained during the first outburst of the black-hole candidate source GRO J1655-40, to search for rapid variability of its X-ray flux. We find no evidence for significant variability of GRO…
We report on the results of a campaign to observe the SXT GRO J1655-40 in outburst using HST, XTE and GRO and AAT. This outburst was qualitatively quite different to other SXT outbursts and to previous outbursts of this source. The onset of…
Aims: The galactic superluminal microquasar GRO J1655-40 started a new outburst in February 2005, after seven years in quiescence, rising to a high/soft state in March 2005. In this paper we study the X-ray spectra during this rise.…
Using the RXTE PCA we discovered deep dips in the X-ray light curves of the black-hole candidates GRO J1655-40 and 4U 1630-47 during outburst. Similar kind of dips for GRO J1655-40 were found in 90s measurements of the RXTE ASM during the…