We performed the scan of the BATSE DISCLA records inspecting 25-50 keV range to pick up soft GRBs. We applied the same technique as in our previous (Stern et al. 2001)1 scan in the 50-300 keV range. We scanned about 1.8 year of the data and found 30 new gamma-ray burst (GRB)s. The total number of soft GRBs in the BATSE data, with the count rate in the 25-50 keV range higher than in the 50-300 keV range, is only 4%. There are about two extremely soft events per year which are invisible about 50 keV and which could constitute a new class of events separate from the GRB phenomenon. We also show that X-ray flashes (XRFs) detected by BeppoSAX have a hardness ratio very similar to that of normal GRBs, supporting a view that XRFs and GRBs are a single phenomenon with a wide spectral variety.
|State||Published - 2005|
|Event||40th Rencontres de Moriond on Very High Energy Phenomena in the Universe, VHEPU 2005 - La Thuile, Italy|
Duration: 12 Mar 2005 → 19 Mar 2005
|Conference||40th Rencontres de Moriond on Very High Energy Phenomena in the Universe, VHEPU 2005|
|Period||12/03/05 → 19/03/05|