GCN Circular 8375
A. Copete, J. Grindlay (Harvard), S. Barthelmy (GSFC) We report on an independent detection of the flare star Algol from Swift-BAT slew data that precedes the BAT detection reported by L. Vetere et al (GCN 8371). On the slew that began on 10/13/08 at 21:16:47 UT and lasted 129sec, ending 4sec before the trigger in spacefraft pointing mode, Algol had an exposure time of 80.60sec and is detected as a high-significance source in both the 15-50keV and 15-150keV energy bands (12.6 and 10.7 sigma, respectively). The calculated location is: RA(J2000) = 03h 08m 11s Dec(J2000) = +40d 59' 42" with an uncertainty of 3.0arcmin (90% radius). The derived 15-50keV band flux is 343 mCrab. Prior to this detection, Algol fell within the BAT slew survey field-of-view in the slews that began at 20:54:02 UT and lasted 158sec, and at 19:57:02 UT and lasted 109sec, but in neither case was it detected at a significance greater than 3.5sigma.