Related papers: IGR J19140+098, a new INTEGRAL transient

INTEGRAL monitoring of the Galactic Plane is revealing a growing number of recurrent X-ray transients, characterised by short outbursts with very fast rise times (~ tens of minutes) and typical durations of a few hours. Here we show that…

We take advantage of the high sensitivity of the IBIS/ISGRI telescope and the improvements in the data analysis software to investigate the nature of the still poorly known X-ray source AX J1910.7+0917, and search for close-by previously…

We report on the discovery of two Fast X-ray Transients (FXTs) from analysis of archival INTEGRAL data. Both are characterized by a remarkable hard X-ray activity above 20 keV, in term of duration (about 15 and 30 minutes, respectively),…

We report here the first results of the spectral and timing analysis of our simultaneous INTEGRAL/RXTE observations of GRS 1915+105. The first observation ever performed with INTEGRAL revealed a new class of variability, where changes of…

Since its launch INTEGRAL has devoted a significant fraction of its observing time to the Galactic plane region. We present the results of INTEGRAL observations of the inner spiral arms of the Galaxy (Norma, Scutum and Sagittarius) with…

GRB 070610 is a typical high-energy event with a duration of 5s.Yet within the burst localization we detect a highly unusual X-ray and optical transient, SwiftJ195509.6+261406. We see high amplitude X-ray and optical variability on very…

We present here the main characteristics of the BHC IGR J17091-3624 outbursts occurred several times since 1994. Since 2003, the source has been extensively observed by INTEGRAL and Swift. In particular, we report results on the last 2011…

About 30% of the sources in the 4th INTEGRAL-IBIS catalogue are unidentified in that they lack an optical counterpart. To be able to classify them, X-ray observations are of crucial importance as they can place tighter constraints on the…

We present the discovery and multi-wavelength characterization of SRGA J181414.6-225604, a Galactic hard X-ray transient discovered during the ongoing SRG/ART-XC sky survey. Using data from the Palomar Gattini-IR survey, we identify a…

IGR J16460+0849 is reported in the 3rd IBIS catalog with the shortest exposure of about 10 ks among all the detected sources, which makes it the most interesting target to be investigated with a deeper exposure. We analyze all available…

The source XTE J1901+014 discovered by the RXTE observatory during an intense outburst of hard radiation and classified as a fast X-ray transient is studied. The source's spectral characteristics in the quiescent state have been…

IGR J18214-1318, a Galactic source discovered by the International Gamma-Ray Astrophysics Laboratory, is a high-mass X-ray binary (HMXB) with a supergiant O-type stellar donor. We report on the XMM-Newton and NuSTAR observations that were…

We identify the periodic transient hard X-ray source GRO J1849-03 with the transient x-ray pulsar GS 1843-02 = X1845-024 based on the detection of x-ray outbursts from X1845-024 coincident with hard x-ray outbursts of GRO J1849--03. Based…

We report on the results of the multiwavelength campaign carried out after the discovery of the INTEGRAL transient IGR J17329-2731. The optical data collected with the SOAR telescope allowed us to identify the donor star in this system as a…

We present detailed spectral and timing analysis of the hard x-ray transient IGR J16358-4726 using multi-satellite archival observations. A study of the source flux time history over 6 years, suggests that lower luminosity transient…

We present further results from our ongoing optical spectrophotometric campaign at the Astronomical Observatory of Bologna in Loiano (Italy) on unidentified hard X-ray sources detected by INTEGRAL. We observed spectroscopically the putative…

The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellite has detected in excess of 1000 sources in the ~20-100 keV band during its surveys of the sky over the past 17 years. We obtained 5 ks observations of 15 unclassified…

The discovery of the X-ray source IGR J17252-3616 by INTEGRAL was reported on 9 February 2004. Regular monitoring by INTEGRAL shows that IGR J17252-3616 is a persistent hard X-ray source with an average count rate of 0.96 counts/s (~6.4…

Context: AXJ1845.0-0433 was discovered by ASCA in 1993 during fast outburst activity characterized by several flares on short timescales. Up to now, the source was not detected again by any X-ray mission. Its optical counterpart is…

We report on the first broad-band (1-200 keV) simultaneous Chandra-INTEGRAL observations of the recently discovered hard X-ray transient IGR J17177-3656 that took place on 2011, March 22, about two weeks after the source discovery. The…