Bibcode
DOI
Castro-Tirado, A. J.; Zapatero-Osorio, M. R.; Gorosabel, J.; Greiner, J.; Heidt, J.; Herranz, D.; Kemp, S. N.; Martínez-González, E.; Oscoz, A.; Ortega, V.; Röser, H.-J.; Wolf, C.; Pedersen, H.; Jaunsen, A. O.; Korhonen, H.; Ilyin, I.; Duemmler, R.; Andersen, M. I.; Hjorth, J.; Henden, A. A.; Vrba, F. J.; Fried, J. W.; Frontera, F.; Nicastro, L.
Bibliographical reference
The Astrophysical Journal, Volume 511, Issue 2, pp. L85-L88.
Advertised on:
2
1999
Journal
Citations
36
Refereed citations
32
Description
We imaged the X-ray error box of GRB 980703, beginning 22.5 hr 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 radio source reported by Frail et al. in
1998, who also detected the optical transient independently of us.
Further imagery revealed the gamma-ray burst (GRB) host galaxy, with
R=22.49+/-0.04 and H=20.5+/-0.25, the brightest so far detected. When
excluding its contribution to the total flux, both the R- and H-band
light curves are well fit by a power-law decay with index alpha~=1.4.
Our data suggest an intrinsic column density in the host galaxy of
~3.5x10^21 cm^-2, which indicates the existence of a dense and gas-rich
medium in which the GRB occurred, thus supporting the hypernova model
scenarios.