We present ground-based optical observations of GRB 020124 starting 1.6 hr after the burst, as well as subsequent Very Large Array and Hubble Space Telescope (HST) observations. The optical afterglow of GRB 020124 is one of the faintest afterglows …
We present sequential optical spectra of the afterglow of GRB 010222 obtained 1 day apart using the Low-Resolution Imaging Spectrometer (LRIS) and the Echellette Spectrograph and Imager (ESI) on the Keck Telescopes. Three low-ionization absorption …
We present radio observations of the afterglow of the bright γ-ray burst GRB 980329 made between 1 month and several years after the burst, a reanalysis of previously published submillimeter data, and late-time optical and near- infrared (NIR) …
Of all the well-localized gamma-ray bursts, GRB 000911 has the longest duration (T$_90$=500 s) and ranks in the top 1% of BATSE bursts for fluence. Here we report the discovery of the afterglow of this unique burst. In order to simultaneously fit our …
Using observations from an extensive monitoring campaign with the Hubble Space Telescope, we present the detection of an intermediate- time flux excess that is redder in color relative to the afterglow of GRB 011121, currently distinguished as the …
Of the cosmological gamma-ray bursts, GRB 011121 has the lowest redshift, z=0.36. More importantly, the multicolor excess in the afterglow detected in the Hubble Space Telescope (HST) light curves is compelling observational evidence of an underlying …
We present a comprehensive study to measure the locations of gamma-ray bursts (GRBs) relative to their host galaxies. In total, we find the offsets of 20 long-duration GRBs from their apparent host galaxy centers by utilizing ground-based images from …
We present millimeter- and submillimeter-wavelength observations and near-infrared K-band imaging toward the bright gamma-ray burst GRB 010222. Over seven different epochs, a constant source was detected with an average flux density of 3.74+/-0.53 …
GRB 970828 was the first well-localized γ-ray burst (GRB) X-ray afterglow for which no optical afterglow was found despite a prompt, deep search down to R$_lim$åisebox-0.5ex 24.5 mag. We report the discovery of a short-lived radio flare within the …
We present a comprehensive sample of all gamma-ray burst (GRB) afterglows with known distances, and we derive their conical opening angles based on observed broadband breaks in their light curves. Within the framework of this conical jet model, we …