Related papers: The Supernova associated with GRB 030329
Over the six years since the discovery of the gamma-ray burst GRB 980425, associated with the nearby (distance, ~40 Mpc) supernova 1998bw, astronomers have fiercely debated the nature of this event. Relative to bursts located at…
The optical afterglow of long-duration GRB 071003 is among the brightest yet to be detected from any GRB, with R ~ 12 mag in KAIT observations starting 42 s after the GRB trigger, including filtered detections during prompt emission.…
It has been claimed recently that Swift has captured for the first time a late-time afterglow re-brightening of clear nonflaring origin after the steep decay of the prompt emission in a long gamma-ray burst (GRB), which may have been…
Gamma Ray Bursts (GRB) observed up to redshifts $z>8$ are fascinating objects to study due to their still unexplained relativistic outburst mechanisms and a possible use to test cosmological models. Our analysis of 77 GRB afterglows with…
In these proceedings, I discuss recent progress in understanding the nature of cosmic gamma-ray bursts (GRB), with the focus on the apparent relation of several GRBs with an energetic subclass of stellar explosions, type Ib/c core-collapse…
GRB 980329 is the brightest gamma-ray burst detected so far with the Wide Field Cameras aboard BeppoSAX, both in gamma-rays and X-rays. With respect to its fluence (2.6 X 10**-5 erg/s/cm**2 in 50 to 300 keV) it would be in the top 4% of…
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at cosmological distances with estimated…
Strong, delayed X-ray line emission is detected in the afterglow of GRB 030227, appearing near the end of the XMM-Newton observation, nearly twenty hours after the burst. The observed flux in the lines, not simply the equivalent width,…
[Abridged] We report the discovery of the near-infrared and optical afterglow of the short-duration gamma-ray burst GRB070724A. The afterglow is detected in i,J,H,K observations starting 2.3 hr after the burst with K=19.59+/-0.16 mag and…
The two brightest and so far the best studied gamma ray bursts (GRBs), 990123 and 080319B, were ordinary, highly collimated GRBs produced in a core collapse supernova explosion within a high-density wind environment and observed from a very…
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.…
Conversion from neutron stars to strange stars as a possible mechanism of cosmological gamma-ray bursts (GRBs) has been discussed in previous works, although the existence of strange stars is still an open question. On the basis of this…
We present ground-based and HST optical observations of the optical transients (OTs) of long-duration Gamma Ray Bursts (GRBs) 060729 and 090618, both at a redshift of z = 0.54. For GRB 060729, bumps are seen in the optical light curves…
We present optical, near-infrared, and X-ray observations of the optical afterglow (OA) of the X-ray rich, long-duration gamma-ray burst GRB 011211. Hubble Space Telescope (HST) data obtained 14, 26, 32, and 59 days after the burst, show…
The optical afterglow of the gamma-ray burst GRB 970508 (z = 0.835) was a few hundred times more luminous than any supernova. Therefore, a name `hypernova' is proposed for the whole GRB/afterglow event. There is tentative evidence that the…
GRB 190829A is the fourth closest gamma-ray burst (GRB) to date ($z=0.0785$). Owing to its wide range of radio, optical, X-ray, and the very-high-energy (VHE) observations by H.E.S.S., it has become an essential new source examined by…
We present the earliest optical imaging observations of GRB 030329 related to SN 2003dh. The burst was detected by the HETE-2 satellite at 2003 March 29, 11:37:14.67 UT. Our wide-field monitoring started 97 minutes before the trigger and…
Afterglow, or long-lived emission, has now been detected from about a dozen well-positioned gamma-ray bursts. Distance determinations made by measuring optical emission lines from the host galaxy, or absorption lines in the afterglow…
We observed the optical afterglow of the bright gamma-ray burst GRB030329 on the nights of 2003 March 29, using the Kiso observatory (the University of Tokyo) 1.05 m Schmidt telescope. Data were taken from March 29 13:21:26 UT to 17:43:16…
The well-sampled afterglows of gamma ray bursts (GRBs) not associated with a supernova (SN) explosion, can be scaled down to a simple dimensionless universal formula, which describes well their temporal behavior. Such SN-less GRBs include…