//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11545 SUBJECT: GRB 110107A detected in ground analysis of BAT slew data DATE: 11/01/08 11:50:43 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings (GSFC/UMBC) on behalf of the Swift-BAT team GRB 110107A occurred at 21:15:51 UTC. It was observed by Fermi GBM (trigger 316127753) and occurred during a Swift slew with BAT event capture. There is a strong source in a mosaic of BAT images at RA, Dec 299.890, 41.889, which is RA (J2000) 19h 59m 33.6s Dec (J2000) +41d 53m 19s with an estimated 90% uncertainty of 3 arcmin radius. The burst was about 100 seconds long, starting at about T-70 sec and lasting until about T+40 sec. The BAT event data ended at about T+21 sec. The burst had multiple peaks, with the largest flux at about T0, the time of the Fermi GBM trigger. The peak count rate in BAT was about 4000 counts/sec. A Swift Target of Opportunity observation has been requested and approved. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11546 SUBJECT: GRB 110107A: Swift-BAT refined analysis DATE: 11/01/08 19:45:24 GMT FROM: Scott Barthelmy at NASA/GSFC J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC) on behalf of the Swift-BAT team: Using the data set from T-70 to T+22 sec from recent telemetry downlinks, we report further analysis of BAT GRB 110107A (a ground-found burst) (Cummings, GCN Circ. 11545). The mask-weighted light curve shows low level multiple overlapping peaks starting at ~T-70 sec and ending at ~T+22 sec. The event-by-event data captured during the slew stops at T+22 sec. Using the on-board raw rates, there is a weak indication that the burst continued out to ~T+45 sec. The time-averaged spectrum from T-70 to T+22 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.58 +- 0.03. The fluence in the 15-150 keV band is at least 5.8 +- 0.5 x 10^-6 erg/cm2. All the quoted errors are at the 90% confidence level. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11547 SUBJECT: GRB 110107A: Swift-XRT Afterglow Candidate DATE: 11/01/08 22:09:10 GMT FROM: Valerio D'Elia at ASDC G. Stratta (ASDC), V. D'Elia (ASDC), P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team: Swift began a target of opportunity observation of GRB 110107A on January 8, 2011 at 15:07 UT, approximately 17.8 hours after the burst detected by Fermi. The GRB was deteced during a Swift slew with BAT event capture. Swift data for these observations utilize Target ID 20157. The XRT began observing the field at 15:12:43 UT, 64.8 ks after the Fermi trigger. Using 2517 s of XRT Photon Counting mode data and 1 UVOT images, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 299.90910, 41.91400 which is equivalent to: RA (J2000):  19 59 38.20 Dec (J2000): +41 54 50.3 with an uncertainty of 3.6 arcsec (radius, 90% confidence). This position is 1.7 arcminutes distant from the BAT position. This position may be improved as more data are received.  The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). The count rate level is (1.2+/-0.2)10^-2 counts/s. We cannot state if the source is fading at this stage and we need to wait for more data. This circular is an official product of the Swift-XRT team. ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11551 SUBJECT: GRB 110107A: Swift/UVOT upper limits DATE: 11/01/10 19:20:46 GMT FROM: Stefan Immler at NASA/GSFC S. Immler (CRESST/UMCP/GSFC) and G. Stratta (ASDC) report on behalf of the Swift/UVOT team: Swift UVOT started observing the field of GRB 110107A on January 8, 2011 at 15:12 UT, approximately T+17.9 hours (Cummings, GCN Circ 11545). No optical afterglow consistent with the XRT position (Stratta et al., GCN Circ. 11547) is detected in individual or merged UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) are: Filter T_start T_stop Exp(s) Mag ----------------------------------------------- v 64,646 75,090 2247 >20.5 u 64,609 74,538 1638 >21.2 ----------------------------------------------- The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.459 mag (Schlegel et al., 1998, ApJS, 500, 525). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11565 SUBJECT: GRB 110107A: Swift-XRT afterglow confirmation DATE: 11/01/13 17:23:16 GMT FROM: Giulia Stratta at ASDC G. Stratta (ASDC) reports on behalf of the Swift-XRT team: Swift performed a second target of opportunity observation of GRB 110107A on January 12, 2011. The XRT began observing the field at 2011-01-12 18:07:47 UT, that is T+420.7 ks (4.87 days) (Cummings, GCN Circ. 11545). Using 2.1 ks of Photon Counting mode data we find that the source has faded down to a 3-sigma upper limit of 0.007 counts/s. Assuming a power law decay starting from the first source detection (Stratta et al., GCN Circ. 11547), the upper limit is consistent with a decay index steeper than alpha = -0.4. The fading nature of the source confirms its afterglow origin. This circular is an official product of the Swift-XRT team.