TITLE: GCN CIRCULAR NUMBER: 76 SUBJECT: BATSE on-board GRB trigger change DATE: 98/05/19 22:34:03 GMT FROM: R Marc Kippen at BATSE/UAH/MSFC RE: BATSE on-board trigger changes The BATSE on-board transient event trigger energy range was changed from channels 2+3 (~50-300 keV) to channels 3+4 (>100 keV) on 19 May, 1998 14:39:54 UT. The revised trigger definition will be enabled for the next several months to increase the chance of detecting Terrestrial Gamma-Ray Flashes (TGFs). The higher trigger energy range will also help to decrease the number of Solar Flare events. This triggering change has been enabled previously and it was found that there is only a small decrease in the sensitivity to classical GRBs.