//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7138 SUBJECT: GRB 071129: Swift detection of a burst DATE: 07/11/29 00:13:36 GMT FROM: Scott Barthelmy at NASA/GSFC C. Pagani (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), F. E. Marshall (NASA/GSFC), J. L. Racusin (PSU), G. Sato (GSFC/ISAS), M. Stamatikos (NASA/ORAU), T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the Swift Team: At 00:03:55 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 071129 (trigger=297628). Swift did not slew to this burst because of the Sun observing constraint (23deg is less than 45 deg). The BAT on-board calculated location is RA, Dec 220.090, -26.659, which is RA(J2000) = 14h 40m 22s Dec(J2000) = -26d 39' 31" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak with a duration of about 30 sec. The peak count rate was ~1000 counts/sec (15-350 keV), at ~5 sec after the trigger. There will be no XRT or UVOT observations of this burst because of the Sun observing constraint. Burst Advocate for this burst is C. Pagani (pagani AT astro.psu.edu). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 7139 SUBJECT: GRB 071129, Swift-BAT refined analysis DATE: 07/11/29 13:07:49 GMT FROM: Scott Barthelmy at NASA/GSFC D. Palmer (LANL), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), C. Pagani (PSU), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+800 sec from recent telemetry downlinks, we report further analysis of BAT GRB 071129 (trigger #297628) (Pagani, et al., GCN Circ. 7138). The BAT ground-calculated position is RA, Dec = 220.039, -26.667 deg, which is RA(J2000) = 14h 40m 09.3s Dec(J2000) = -26d 39' 60" with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 55%. The mask-weighted light curve shows three long, low, smooth peaks. The first starts at ~T-10 sec, peaks at ~T+5 sec, and then roughly exponentially decays t a minimum around T+100 sec. The second peak is more symmetric rising to a peak at ~T+180 sec and decaying back to baseline around T+300 sec. The third weaker peak reaches a max around T+400 sec and is over by around T+450 sec. T90 (15-350 keV) is 420 +- 100 sec (estimated error including systematics). The time-averaged spectrum from T-5.6 to T+522.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.94 +- 0.16. The fluence in the 15-150 keV band is 3.5 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+5.83 sec in the 15-150 keV band is 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. This burst satisfies Sakamoto/Ukwatta Swift-BAT possible high-z criteria: 1) Power law photon index = 1.94 (PL photon index < 2) 2) 1-s peak photon flux = 0.9 (1-s peak photon flux < 1.0 ph/cm2/s) 3) Light curve variance = 1.5e-6 (Variance < 0.0001) 4) T90/(Peak photon flux) = 480 (T90/(Peak photon flux) > 200) Based on a limited sample of bursts, these criteria yield an 85% chance it has a redshift greater than 3.5.