GRB 070429

S. D. Barthelmy (GSFC), C. B. Markwardt (GSFC/UMD),
K. L. Page (U Leicester), D. M. Palmer (LANL), G. Sato (GSFC/ISAS),
M. Stamatikos (NASA/ORAU) and R. L. C. Starling (U Leicester) report
on behalf of the Swift Team:

At 01:35:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 070429 (trigger=277571).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 297.687, -32.388 which is 
   RA(J2000)  =  19h 50m 45s
   Dec(J2000) = -32d 23' 16"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is typical for image trigger GRBs,
the BAT light curve shows little obvious variation.  A detailed
light curve will require the data downlinked via Malindi. 

The XRT began observing the field at 01:37:42 UT, 153 seconds after the
BAT trigger. XRT found a fading, uncatalogued X-ray source
located at RA, Dec 297.7034, -32.4052 which is
   RA(J2000)  =  19h 50m 48.8s
   Dec(J2000) = -32d 24' 18.7"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). 
This location is 79 arcseconds from the BAT on-board position,
within the BAT error circle. The initial flux in the 2.5s image
was 2.9e-09 erg/cm2/s (0.2-10 keV). 

UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 161 seconds after the BAT trigger. No afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 18.5 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.17 magnitudes.

E.S. Rykoff (U Mich), B. E. Schaefer (Louisiana State), H. Swan (U 
Mich), report on behalf of the ROTSE collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, 
responded to GRB 070429 (Swift trigger 277571, GCN 6355
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 , Barthelmy, et 
al), producing images beginning 6.7 s after the GCN notice time. An 
automated response took the first image at 01:36:46.7 UT, 96.6 s after 
the burst, under good conditions. We took 10 5-sec, 10 20-sec exposures; 
imaging is ongoing. These unfiltered images are calibrated relative to 
USNO A2.0 (R).

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma BAT error circle or the XRT error circle, for both single images 
and coadding into sets of 10; however, we are limited as the field is 
somewhat crowded. Individual images have limiting magnitudes ranging 
from 16.1-17.1; we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
01:36:46.7   01:36:51.7         5     16.2           96.6       N
01:36:46.7   01:38:04.4        77     17.3           96.6       Y
01:38:19.4   01:43:08.1       288     18.0          189.3       Y

Nobody from UVOT or PSU was on the burst telecon, so we looked at the  
UVOT data, saw nothing, and used the automatic paragraph.

There was nobody to check the temperature, so that should be done  
when someone who can do it reads this.