New Soft Gamma Repeater SGR 0501+4516

The Authors report on behalf of the Swift Team On 2008-08-22, at 12 41 59, 13 09 04 UT, 13 12 52, and 17 29 29, Swift-BAT triggered on four short (less than 128 ms) bursts of soft gamma-rays (no significant flux above 100 keV) with an afterglow located by XRT at RA(J2000) = 05h 01m 6.78s Dec(J2000) = +45d 16' 34.0" with an uncertainty of 2.6 arcseconds (radius, 90% containment). (GCN 8112, Holland et al.; GCN 8113, Barthelmy et al.; GCN 8115, Palmer & Barthelmy) The repetition, the short, soft nature of the pulses, and the proximity of the source to the Galactic plane allow us to identify this source as a previously unknown Soft Gamma Repeater SGR 0501+4516.