GRB 071129

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.)

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
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 ).  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.