• Publications
  • Influence
An unusual supernova in the error box of the γ-ray burst of 25 April 1998
TLDR
We report the discovery of transient optical emission in the error box of the γ-ray burst GRB980425, the light curve of which was very different from that of previous optical afterglows associated with β�-ray bursts. Expand
  • 541
  • 56
Long γ-ray bursts and core-collapse supernovae have different environments
When massive stars exhaust their fuel, they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an evenExpand
  • 578
  • 55
  • PDF
A hypernova model for the supernova associated with the γ-ray burst of 25 April 1998
The discovery of the unusual supernova SN1998bw, and its possible association with the γ-ray burst GRB 980425, provide new insights into the explosion mechanism of very massive stars and the originExpand
  • 483
  • 48
  • PDF
A very energetic supernova associated with the γ-ray burst of 29 March 2003
Over the past five years evidence has mounted that long-duration (>2 s) γ-ray bursts (GRBs)—the most luminous of all astronomical explosions—signal the collapse of massive stars in our Universe. ThisExpand
  • 972
  • 46
  • PDF
No supernovae associated with two long-duration γ-ray bursts
It is now accepted that long-duration γ-ray bursts (GRBs) are produced during the collapse of a massive star1,2. The standard ‘collapsar’ model3 predicts that a broad-lined and luminous type IcExpand
  • 302
  • 44
  • PDF
GRB 080913 AT REDSHIFT 6.7
TLDR
We report on the detection by Swift of GRB 080913, and subsequent optical/near-infrared follow-up observations by GROND, which led to the discovery of its optical/NIR afterglow and the recognition of its high-z nature via the detection of a spectral break between the i' and z' bands. Expand
  • 175
  • 43
  • PDF
An optical supernova associated with the X-ray flash XRF 060218
Long-duration γ-ray bursts (GRBs) are associated with type Ic supernovae that are more luminous than average and that eject material at very high velocities. Less-luminous supernovae were notExpand
  • 383
  • 38
  • PDF
Low-resolution Spectroscopy of Gamma-ray Burst Optical Afterglows: Biases in the Swift Sample and Characterization of the Absorbers
We present a sample of 77 optical afterglows (OAs) of Swift detected gamma-ray bursts (GRBs) for which spectroscopic follow-up observations have been secured. Our first objective is to measure theExpand
  • 277
  • 28
  • PDF
The Metamorphosis of SN 1998bw
We present and discuss the photometric and spectroscopic evolution of the peculiar SN 1998bw, associated with GRB 980425, through an analysis of optical and near-IR data collected at ESOLa Silla. TheExpand
  • 262
  • 25
  • PDF
IFU observations of the GRB 980425/SN 1998bw host galaxy : emission line ratios in GRB regions
Context. The collapsar model predicts that the progenitors of Gamma-ray Bursts (GRBs) are metal poor in Fe group elements. The existence of low metallicity stellar populations could manifest itselfExpand
  • 83
  • 19
  • PDF