[ Previous | Next | ADS ]

New Soft Gamma Repeater SGR 0501+4516

ATel #1676; S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), O. Godet (U Leicester), C. Guidorzi (INAF-OAB), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester), C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), M. Perri (ASDC), T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-IASFPA), R. L. C. Starling (U Leicester), G. Stratta (ASDC), T. N. Ukwatta (GSFC/GWU), and L. Vetere (PSU)
on 22 Aug 2008; 21:04 UT
Credential Certification: David M. Palmer (palmer@lanl.gov)

Subjects: Soft Gamma-ray Repeater

Referred to by ATel #: 1678, 1683, 1692, 1837, 4374, 6000

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.

The ROSAT source 1RXS J050107.9+451631, with a catalogued location 12.2 arcsec from the SGR location and a 13 arcsec uncertainty, may be a previous detection of quiescent flux from this object.