{
  "bibcode": "2020GCN.28599....1K",
  "body": "H. A. Krimm (NSF), S. D. Barthelmy (GSFC),\nJ. R. Cummings (CPI), S. Laha (GSFC/UMBC),\nA. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nT. Sakamoto (AGU), M. Stamatikos (OSU),\nT. N. Ukwatta (LANL) (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry\ndownlink, we report further analysis of SGR 1830-0645 (trigger #999571)\n(Page et al., GCN Circ. 28594).  The BAT ground-calculated position is\nRA, Dec = 277.697, -6.761 deg which is\n   RA(J2000)  =  18h 30m 47.3s\n   Dec(J2000) = -06d 45' 40.0\"\nwith an uncertainty of 2.9 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 89%.\n\nThe mask-weighted light curve shows a single-pulse structure that starts\nat ~T0, peaks at ~T+0.005 s, and ends at ~T+0.008 s. There may be another\nshort pulse (~ 10 ms) at ~ T-2.76 s, which has an image significance\nof ~ 5.1 sigma in 15-25 keV. T90 (15-350 keV) is ~0.008 sec\n(due to the extremely short duration, standard bayesian block analysis\ndoes not produce a meaningful uncertainty).\n\nThe time-averaged spectrum from T+0.00 to T+0.008 sec is best fit by\na simple power-law model.  The power law index of the time-averaged\nspectrum is 2.22 +- 0.47.  The fluence in the 15-150 keV band\nis 7.8 +- 2.5 x 10^-9 erg/cm2. The 1-sec peak photon flux measured\nfrom T+0.00 sec in the 15-150 keV band is 17.2 +- 4.8 ph/cm2/sec.\n\nA single blackbody fit to the time-averaged spectrum shows the blackbody\ntemperature of 9.3 +- 2.1 keV (chi squared 28.52 for 57 d.o.f.).\nAll the quoted errors are at the 90% confidence level.\n\nThe spectral and temporal properties are more consistent with an SGR,\ninstead of a short GRB.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/999571/BA/",
  "circularId": 28599,
  "createdOn": 1602437807000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "SGR 1830-0645: Swift-BAT refined analysis",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>"
}