//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9812 SUBJECT: GRB 090815: Fermi GBM detection DATE: 09/08/15 13:11:29 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 07:12:12.45 UT on 15 August 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090815 (trigger 272013134 / 090815300). The on-ground calculated location, using the GBM trigger data, is RA = 41.7, DEC = -2.0 (J2000 degrees, equivalent to 02h 47m, -02d 00'), with an uncertainty of 7.6 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 87 degrees. The GBM light curve shows two broad pulses with a duration (T90) of about 200 s (8-1000 keV). The time-averaged spectrum from T0-5.120 s to T0+24.576 s is well fit by a simple power law function with index -1.5 +/- 0.1 (chi squared 261 for 241 d.o.f.). The event fluence (8-1000 keV) in this time interval is (3.4 +/- 0.3)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+ 3.072 s in the 8-1000 keV band is 1.9 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9813 SUBJECT: GRB 090815B: Fermi GBM detection DATE: 09/08/15 14:48:04 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 10:30:41.85 UT on 15 August 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090815B (trigger 272025043 / Y090815438). The on-ground calculated location, using the GBM trigger data, is RA = 21.4, DEC = 53.4 (J2000 degrees, equivalent to 01h 26m, 53d 24'), with an uncertainty of 5.7 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 82 degrees. The GBM light curve consists of two peaks with a duration (T90) of about 30 s (8-1000 keV). The time-averaged spectrum from T0-7.168 s to T0+23.552 s is well fit by a power law function with an exponential high energy cutoff. The power law index is -1.89 +/- 0.12 and the cutoff energy, parameterized as Epeak, is 15.1 +/- 10.8 keV (chi squared 297 for 238 d.o.f.). The event fluence (8-1000 keV) in this time interval is (5.05 +/- 0.25)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+16.384 s in the 8-1000 keV band is 14.4 +/- 0.5 ph/s/cm^2. A Band function fits the spectrum equally well (chi squared 296 for 237 d.o.f.) with Epeak= 18.6 +/- 9.6 keV, alpha = -1.82 +/- 0.19 and beta = -2.7 +/- 0.4. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9824 SUBJECT: GRB 090815C: Swift refined analysis DATE: 09/08/17 20:41:44 GMT FROM: Scott Barthelmy at NASA/GSFC J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), P.A. Evans (U. Leicester) on behalf of the Swift Team: At 23:21:39 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090815C (trigger=360068). No GCN Notices were issued because the trigger was below the normal acceptance level. Also, the spacecraft did not execute an automated slew to the location because of an Earth observing constraint. Later, ground-processing using the full data set T-60 to T+303 sec determined the location to be RA, Dec = 64.490, -65.943 deg, which is RA(J2000) = 04h 17m 57.6s Dec(J2000) = -65d 56' 33.5" with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 76%. The BAT mask-weighted light curve shows a single weak peak. T90 (15-350 keV) is 0.6 +- 0.3 sec (estimated error including systematics). The time-averaged spectrum from T-0.0 to T+0.7 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.90 +- 0.47. The fluence in the 15-150 keV band is 4.4 +- 1.2 x 10^-8 erg/cm2. The 1-sec peak photon flux measured from T-0.18 sec in the 15-150 keV band is 0.6 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/360068/BA/ Based on the ground-processing of the full BAT data, a ToO was executed 6.1 hours after the trigger. Swift-XRT obtained 4.3 ks of Photon Counting (PC) mode data, from T0+22 ks to T0+56 ks. No source is found in the BAT error circle, with a 3-sigma upper limit of 1.9 x 10^-3 ct/sec; for a typical GRB, this corresponds to an upper limit on the observed 0.3-10 keV flux of 7 x 10^-14 erg cm^-2 s^-1.