////////////////////////////////////////////////////////////////////////
TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2914
SUBJECT: GRB041226: Swift-BAT detection of a burst
DATE:    04/12/26 23:31:39 GMT
FROM:    Hans Krimm at NASA-GSFC  <krimm@milkyway.gsfc.nasa.gov>

H. Krimm (GSFC/USRA), D. Palmer (LANL), S. Barthelmy (GSFC),
L. Barbier (GSFC), M. Chester (PSU), J. Cummings (GSFC), E. Fenimore (LANL),
N. Gehrels (GSFC), D. Hinshaw (GSFC), D. Hullinger (GSFC/UMD),
C. Markwardt (GSFC/UMD), K. McLean (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC), G. Sato (ISAS), M. Suzuki (Saitama), G. Tagliaferri (OAB),
J. Tueller (GSFC), A. Wells (U Leicester)
on behalf of the Swift-BAT team:

At 20:34:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located on-board GRB041226.  The spacecraft did not autonomously slew
to the burst since automated slewing was not yet enabled.

The BAT ground-calculated location is RA,Dec 79.544,73.349 (J2000)
with an uncertainty of 6 arcmin (radius, 3-sigma, including a systematic
uncertainty).  The lightcurve is multi-peaked with a main emission duration
of ~20 s, with 4 counts/cm^2 fluence and a peak (1 second interval)
of ~0.5 counts/cm^2/s in the 15-350 keV band.
-- 
-------------------------------------
Dr. Hans A. Krimm
Universities Space Research Association
NASA Goddard Space Flight Center
Code 661,  LHEA
Greenbelt, MD  20771
USA
301-286-6955
fax 301-286-1684

////////////////////////////////////////////////////////////////////////
TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2915
SUBJECT: GRB041226: ROTSE-III Optical Observations
DATE:    04/12/27 03:02:30 GMT
FROM:    Eli Rykoff at U of Michigan/ROTSE  <erykoff@umich.edu>

E. Rykoff (U. Michigan) reports on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to Swift 
GRB041226 (GCN #2914).  An automatic response was initiated during early 
twilight hours.  The first usable image taken at 27 Dec. 00:46:47 UT, 
4.2 hours after the burst.  We took 300 20-s exposures.  All the images 
were taken with >99% moon illumination.  The unfiltered images were 
calibrated relative to USNO A2.0.  Individual images have limiting 
magnitudes improving from 15 to 16.8 as the sky darkened.  Comparison to 
DSS (second epoch) reveals no new sources within the 3-sigma error 
circle to a limiting magnitude of 16.1 for stacks of 10 images taken 4.2 
hours after the burst and 17.7 for stacks of 10 images taken 5 hours 
after the burst.

////////////////////////////////////////////////////////////////////////
TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2961
SUBJECT: GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
DATE:    05/01/18 19:01:22 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

A. J. Castro-Tirado, M. Jelínek, A. de Ugarte Postigo,
(IAA-CSIC Granada), S. Vitek (Czech Technical University, 
Prague), P. Kubanek  (Astronomical Institute of the Academy 
of Sciences, Ondrejov), T. J. Mateo Sanguino (Universidad 
de Huelva), J. M. Castro Cerón (U. Copenhagen), T. Soria 
(EELM-CSIC, Málaga) and J. Fabregat (Universidad de Valencia)

report:
 
The BOOTES-2 very wide field camera, located at the Estación
Experimental de La Mayora (EELM-CSIC) in Málaga, observed 
the two regions of the sky containing the SWIFT/BAT error 
boxes for GRB 041224 (Barthelmy et al. GCN 2908) and GRB 
041226 (Krimm et al. GCN 2914) as part of its routine 
observing schedule. For GRB 041224 a 30 s exposure started 
at 20:21:00 UT (3 s after the onset of the 50 s long burst), 
with the following frame starting at 20:22:00 UT. For GRB
041226 the 30 s exposure started at 20:34:00 (19 s prior to 
the onset of the 20 s main emission peak). Limiting (unfiltered) 
magnitudes of 8.5 and 7.0 respectively (due to the presence 
of the full moon) are derived for any promt optical flash
arising from either of these two events.

This message can be quoted.