STScI Preprint #1205

The Gamma Ray Bursts GRB970228 and GRB970508: What have we learnt?

We examine what we regard as key observational results on GRB 970228 and GRB 970508 and show that the accumulated evidence strongly suggests that -ray bursts (GRBs) are cosmological fireballs.

We further show that the observations suggest that GRBs are not associated with the nuclear activity of active galactic nuclei, and that late-type galaxies are more prolific producers of GRBs.

We suggest that GRBs can be used to trace the cosmic history of the star-formation rate. Finally, we show that the GRB locations with respect to the star-forming regions in their host galaxies and the total burst energies can be used to distinguish between different theoretical models for GRBs.

Status:

Appeared in: Huntsville Symposium on Gamma-Ray Bursts 4:483-488, 1998

Affiliations:

¹) Space Telescope Science Institute 3700 San Martin Drive Baltimore, MD 21218 USA

²) Instituto di Technologie e Studio delle Radiazioni Extraterrestri C.N.R., Via Gobetti 101, I-40129 Bologna, Italy

³) Astronomical Institute "Anton Pannekoek", University of Amsterdam, & Center for High Energy Astrophysics, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands

⁴) Physics Department, University of Alabama in Huntsville, Huntsville, AL 35899, USA

⁵) Universities Space Research Association, NASA Marshall Space Flight Center, ES-84, Huntsville, AL 35812, USA