The rapid decay of the optical emission from GRB 980326 and its possible implications | Instituto de Astrofísica de Andalucía

DOI:

Publication date:

01/01/1998

Main author:

Groot P.J.

IAA authors:

Castro-Tirado A.J.

Authors:

Groot P.J., Galama T.J., Vreeswijk P.M., Wijers R.A.M.J., Pian E., Palazzi E., Van Paradijs J., Kouveliotou C., In 'T Zand J.J.M., Heise J., Robinson C., Tanvir N., Lidman C., Tinney C., Keane M., Briggs M., Hurley K., Gonzalez J.-F., Hall P., Smith M.G., Covarrubias R., Jonker P.G., Casares J., Masetti N., Frontera F., Feroci M., Piro L., Costa E., Smith R., Jones B., Windridge D., Bland-Hawthorn J., Veilleux S., Garcia M., Brown W.R., Stanek K.Z., Castro-Tirado A.J., Gorosabel J., Greiner J., Jäger K., Böhm A., Fricke K.J.

Journal:

Astrophysical Journal

Publication type:

Article

Volume:

502

Pages:

L123-L127

Number:

Abstract:

We report the discovery of the optical counterpart to GRB 980326. Its rapid optical decay can be characterized by a power law with exponent -2.10 ± 0.13 and a constant underlying source at Rc = 25.5 ± 0.5. Its optical colors 2.1 days after the burst imply a spectral slope of -0.66 ± 0.70. The γ-ray spectrum as observed with BATSE shows that it is among the 4% softest bursts ever recorded. We argue that the rapid optical decay may be a reason for the nondetection of some low-energy afterglows of GRBs.

Database:

SCOPUS

Keywords:

Gamma rays: bursts; Gamma rays: observations; Radiation mechanisms: nonthermal