Related papers: A Luminous Companion to SGR 1806-20

We report the discovery of the nearby long, soft GRB 100316D, and the subsequent unveiling of its host galaxy and associated supernova. We study the extremely unusual prompt emission with time-resolved gamma-ray to X-ray spectroscopy and…

Over a decade ago it was established that the remarkable high energy transients, known as soft gamma-ray repeaters (SGRs), are a Galactic population and originate from neutron stars with intense (<~ 10^15 G) magnetic fields ("magnetars").…

We report on bursts from the Soft Gamma-Ray Repeater SGR 1806--20 detected with INTEGRAL in October 2003, during a period of moderate activity of the source. The spectral and temporal properties of 21 short bursts are consistent with those…

Earlier we had suggested that G10.0-0.3, a non-thermal nebula, most likely an old supernova remnant (SNR), was associated with the soft gamma repeater (SGR) SGR 1806-20. Here we present new radio images obtained at the Very Large Array…

We report on the discovery of the radio, infrared and optical transient coincident with an X-ray transient proposed to be the afterglow of GRB 980703. At later times when the transient has faded below detection, we see an underlying galaxy…

We present late-time observations of the site of the Type Ibn supernova (SN) 2006jc acquired with the Hubble Space Telescope Advanced Camera for Surveys. A faint blue source is recovered at the SN position with brightness…

Despite much theoretical and observational progress, there is no known firm upper limit to the masses of stars. Our understanding of the interplay between the immense radiation pressure produced by massive stars in formation and the opacity…

We imaged the X-ray error box of GRB 980703, beginning 22.5 hours after the gamma--ray event, in both the optical R and near-infrared H bands. A fading optical/IR object was detected within the X-ray error box, coincident with the variable…

Of the fourteen gamma-ray bursts (GRBs) localized to better than 2' radius with the SXC on HETE-2, only two lack optical afterglow detections, and the high recovery rate among this sample has been used to argue that the fraction of truly…

We present the results of an analysis of the quiescent X-ray emission from the Soft Gamma-Ray Repeater SGR1806-20, taken during an INTEGRAL ultra-deep survey of the Galactic Center region in autumn 2003. The total effective exposure time…

We report the discovery of the host galaxy of dark burst GRB080607 at z_GRB=3.036. GRB080607 is a unique case of a highly extinguished (A_V~3 mag) afterglow that was yet sufficiently bright for high-quality absorption-line spectroscopy. The…

Soft gamma-ray repeaters (SGRs) are a rare type of gamma-ray transient sources that are ocasionally detected as bursts in the high-energy sky. They are thought to be produced by magnetars, young neutron stars with very strong magnetic…

We made a 100 ks observation of the Sagittarius (Sgr) B1 region at (l, b) = (0.5, -0.1) near to the Galactic center (GC) with the Suzaku/XIS. Emission lines of S XV, Fe I, Fe XXV, and Fe XXVI were clearly detected in the spectrum. We found…

Since January 1997, we have monitored 15 GRB fields, detecting 6 optical/IR afterglows. For GRB 970508, we derive a power-law decay exponent alpha = -1.19 (R-band). The luminosity of the host galaxy L relative to the characteristic…

We use the cannonball model of gamma ray bursts (GRBs) and public data from the first day of observations of GRB 090618 to predict its X-ray and optical lightcurves until very late times, and, in particular, the emergence of a photometric…

The supernova SN 2006aj associated with GRB 060218 is the second-closest GRB-SN observed to date (z=0.033). We present Very Large Telescope, Liverpool Telescope, and Katzman Automatic Imaging Telescope multi-color photometry of SN 2006aj.…

On 2006 May 5, a four second duration, low energy, ~10^49 erg, Gamma-Ray Burst (GRB) was observed, spatially associated with a z=0.0894 galaxy. Here, we report the discovery of the GRB optical afterglow and observations of its environment…

We report the discovery of persistent hard X-ray emission extending up to 150 keV from the soft gamma-ray repeater SGR 1806-20 using data obtained with the INTEGRAL satellite in 2003-2004. Previous observations of hard X-rays from objects…

We report on follow-up observations of the GRB 060927 using the ROTSE-IIIa telescope and a suite of larger aperture ground-based telescopes. An optical afterglow was detected 20 s after the burst, the earliest rest-frame detection of…

We present a Chandra and HST study of IC 10 X-1, the most luminous X-ray binary in the closest starburst galaxy to the Milky Way. Our new hard X-ray observation of X-1 confirms that it has an average 0.5-10 keV luminosity of 1.5e38 erg/s,…