GCN Circular 4137

GRB 051022 (=H3950):  SXC Flight Localization is Valid

K. Tanaka, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley,
on behalf of the HETE Science Team;

M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, N. 
Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka, Y. 
Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki, S. 
Sugita, M. Suzuki, T. Tamagawa, and A. Yoshida, on behalf of the HETE 
WXM Team;

N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek, J. 
Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga, R. 
Manchanda, and G. Pizzichini, on behalf of the HETE Operations and 
HETE Optical-SXC Teams;

M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE 
FREGATE Team;

report:


The HETE team, after reviewing the the real-time messages from HETE 
regarding GRB 051022(=H3950), believes that the SXC real-time 
localization of this burst is valid.  As reported in GCN Notices 
beginning 118 seconds after the initial trigger and in GCN Circular 
4131
Not found
 
 
, the SXC real-time localization can be described as a circle 
centered at

RA =  23h 56m 00s, DEC = +19d 35' 51" (J2000)

with a 90% confidence error radius of 2.5 arcminutes.

This SXC localization corresponds not only to the highest correlation 
peak in the WXM error circle, but also to the highest correlation 
peak in the entire SXC field-of-view.  Therefore GRB 051022 was 
sufficiently bright in soft X-rays that the SXC position was 
determined independently of the WXM result.

In addition, there is good reason to believe that the duration of GRB 
051022 is > 2-4 minutes and that there are periods of low emission 
during the X-ray prompt emission.  These indications, combined with 
the upper limit of  R > 20 by Cenko et al (GCN 4134
Not found
 
 
), suggest that 
searches at NIR and infrared wavelengths for a high redshift object 
in the SXC error region would be of interest.