GCN Circular 11436

J. R. Cummings (GSFC/UMBC/CRESST), D. M. Palmer (LANL),
S. D. Barthelmy (GSFC), and T. Sakamoto (GSFC/UMBC/CRESST) on
behalf of the BAT team,

Valentin Pal'shin (Ioffe Inst) and K. Hurley (UCB) on behalf of
the IPN,

V. Connaughton, M.S. Briggs, and C.A. Meegan on behalf of the
Fermi GBM team,

A. von Kienlin, G. Lichti, and A. Rau, on behalf of the
INTEGRAL SPI-ACS GRB team,

A. P. Beardmore (U Leicester) and J. A. Kennea (PSU) on behalf of
the Swift-XRT team,

K. Yamaoka, M. Ohno, Y. Hanabata, Y. Fukazawa, T. Takahashi,
M. Tashiro, Y. Terada, T. Murakami, and K. Makishima, on behalf of
the Suzaku WAM team,

J. Goldsten, on behalf of the MESSENGER NS GRB team:


At 15:39:31 UTC, Swift-BAT detected a rate increase due to GRB 101129A
(BAT trigger #439471. Only a sub-threshold image source was found
onboard.  This event corresponds to Fermi GBM trigger #312737973. The
IPN was alerted.  In ground analysis, the source was detected with
slightly greater confidence at RA, Dec 155.921, -17.645 which is:

RA (J2000)       10h 23m 41s
Dec (J2000)    -17d 38m 42s

with an estimated uncertainty radius of 3 arcmin (90% containment).
Correlation of Swift-BAT counting rates and SPI-ACS counting rates,
and SPI-ACS with Messenger yielded intersecting annuli consistent with
this position. The burst was also detected by Suzaku-WAM.

As seen in BAT, the burst consisted of a single pulse with a T90 of about
0.35 +- 0.05 sec.

The burst was faint and short. The low-number statistics in BAT make a
fit to the spectrum very uncertain. The photon index was approximately
0.8 +- 0.5.  The fluence was approximately (9 +- 5) x 10^-08 ergs/cm^2.

A Swift TOO observation was executed at 11 hours after the burst.  The
location of the burst was observed by the Swift-XRT and Swift-UVOT for
a total of about 1400 seconds.  No afterglow was detected.  No further
observations are planned.