Related papers: GRB Observed by IBIS/PICsIT in the MeV Energy Rang…
The Milagrito collaboration recently reported evidence for emission of very high energy gamma-rays in the TeV range from one of the BATSE GRBs, GRB 970417a. Here I discuss possible interpretations of this result. Taking into account the…
We present the results of the spectral analysis of the public data of 438 Gamma Ray Bursts (GRBs) detected by the Fermi Gamma ray Burst Monitor (GBM) up to March 2010. For 432 bursts we could fit the time integrated spectrum. In 318 cases…
The spectrometer SPI, one of the two main instruments of the INTEGRAL spacecraft, offers significant gamma-ray burst detection capabilities. In its 35 deg (full width) field of view SPI is able to localise gamma-ray bursts at a mean rate of…
MeV gamma-rays provide a unique window for the direct measurement of line emissions from radioisotopes, but observations have made little significant progress after COMPTEL/{\it CGRO}. To observe celestial objects in this band, we are…
We present a complete sample of 29 GRBs for which it has been possible to determine temporal breaks (or limits) from their afterglow light curves. We interpret these breaks within the framework of the uniform conical jet model,…
It is widely accepted that the prompt transient signal in the 10 keV - 10 GeV band from gamma-ray bursts (GRBs) arises from multiple shocks internal to the ultra-relativistic expansion. The detailed understanding of the dissipation and…
During the first observing run of LIGO, two gravitational wave events and one lower-significance trigger (LVT151012) were reported by the LIGO/Virgo collaboration. At the time of LVT151012, the INTErnational Gamma-Ray Astrophysics…
A bright, long gamma-ray burst (GRB) was detected and localized by the instruments on board the High Energy Transient Explorer 2 satellite (HETE-2) at 02:44:19.17 UTC (9859.17 s UT) on 2002 August 13. The location was reported to the GRB…
We have investigated the MeV behaviour of the \gray blazars 3C~454.3 and CTA 102 by analyzing all COMPTEL observations of this sky region during the complete CGRO mission. Both sources are detected by COMPTEL at the upper COMPTEL energies;…
We present results of spectral and timing analysis of the fast X-ray transient XTE J1901+014 based on data of the RXTE and INTEGRAL observatories. With the INTEGRAL/ISGRI the source was detected at a significance level of 20$\sigma$ with…
Early results from the INTEGRAL Core Program, for a sample of eight persistently bright neutron star low mass X-ray binaries in the energy range from 5 keV to 200 keV are presented. It is shown that INTEGRAL efficiently detects sources and…
Since its early phases of operation, the AGILE mission is successfully observing Gamma Ray Bursts (GRBs) in the hard X-ray band with the SuperAGILE imager and in the MeV range with the Mini-Calorimeter. Up to now, three firm GRB detections…
Since its discovery in 1992, the superluminal X-ray transient GRS 1915+105 has been extensively observed in an attempt to understand its behaviour. We present here first results from a multi-wavelength campaign undertaken from July to…
We study the GRB 081008 environment with simultaneous high- and low-resolution spectroscopy using UVES and FORS2 data acquired ~5 hr after the Swift trigger. The interstellar medium (ISM) of the host galaxy at z=1.9683 is constituted by at…
We present systematic spectral analyses of GRBs detected with the Burst and Transient Source Experiment (BATSE) onboard the Compton Gamma-Ray Observatory (CGRO) during its entire nine years of operation. This catalog contains two types of…
We present a first INTEGRAL observation of the 42s transient X-ray pulsar EXO 2030+375 with IBIS/ISGRI. The source was detected during Cyg X-1 observations in December 2002. We analyzed observations during the outburst period from 9 to 21…
Context. Gamma-ray bursts (GRBs) can be detected at cosmological distances and therefore can be used to study the contents and phases of the early Universe. The 4-150 keV wide-field trigger camera ECLAIRs to fly on board the Space-based…
The number of Gamma-Ray Bursts (GRBs) detected at high energies ($\sim\,0.1-100$ GeV) has seen a rapid increase over the last decade, thanks to observations from the Fermi-Large Area Telescope. The improved statistics and quality of data…
We present results from VERITAS observations of the BL Lac object PG 1553+113 spanning the years 2010, 2011, and 2012. The time-averaged spectrum, measured between 160 and 560\,GeV, is well described by a power law with a spectral index of…
We report optical observations of the GRB 980329 error box which represent the second earliest detection of the GRB 980329 optical transient. We determine R = 23.7 $\pm$ 0.5 mag on 29.89 March, which is consistent with R = 23.6 $\pm$ 0.2…