{
  "bibcode": "2003GCN..2306....1I",
  "body": "RXTE PCA Observations of SGR 1806-20 Region\n\nA. Ibrahim (GWU/GSFC), C. Markwardt (UMD/GSFC), J. Swank (GSFC), \nK. Hurley (UCB), T. Cline (GSFC), & W. Parke (GWU)\n\nReport:\n\nIn response to the burst activity reported by IPN on Jul 14 (GCN\n2297), we pointed the RXTE PCA at the position of SGR 1806-20 on Jul\n15, 11:35-12:20 UT.  A 0.4 mCrab pulsed flux was detected with a\nperiod of 5.54 s +/- 0.01 s.  The PCA saw 3.5 mCrab total flux, but as\nmuch as half is due to Galactic ridge emission in the field of view,\nso that the pulsed fraction could exceed 20%.  The large difference\nbetween the pulse period and the last observed pulse period of SGR\n1806-20 (Woods et al. 2002, ApJ, 576, 381) suggests that a new pulsar\nis present.  There are no known pulsars with that period in the 1.2\ndeg radius field of view of the PCA and we can rule out the nearby\ncandidate SGR 1801-23 (Cline et al. 2000, ApJ, 531, 407).  If the new\npulsar were responsible for the recent bursts, there would be three\nSGRs in a small region. However it is possible that both SGR 1806-20\nand another pulsar are active simultaneously.  PCA scanning\nobservations are planned.\n\nThis message is citeable.",
  "circularId": 2306,
  "createdOn": 1058496800000,
  "email": "craigm@milkyway.gsfc.nasa.gov",
  "subject": "RXTE PCA Observations of SGR1806-20 Region",
  "submitter": "Craig Markwardt at GSFC  <craigm@milkyway.gsfc.nasa.gov>"
}