GCN Circular 1508

GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC

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

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

Y. Shirasaki, C. Graziani, M. Matsuoka, T. Tamagawa, K. Torii, T. 
Sakamoto, A. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, and T. 
Donaghy, on behalf of the HETE WXM Team;

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

write:

At 14:57:35.82 UTC (53855.82 s UT) on 19 Aug 2002, the HETE FREGATE, 
WXM, and SXC instruments detected event H2275, a moderately bright, 
long GRB. In the FREGATE 8-40 keV band, the burst had a duration of 
~20 seconds, and a peak brightness of ~5x Crab. A GCN Burst Alert 
Notice was disseminated 55s after the burst. No real-time optical 
camera aspect was generated at the time of the burst; thus, no WXM 
real-time localization could be disseminated.  Ground analysis of the 
optical camera data, and of the WXM data for the burst, produced a 
refined location which was reported in a GCN Position Notice issued 
98 minutes after the burst. The WXM location can be expressed as a 
90% confidence circle that is 7 arcminutes in radius and is centered 
at

WXM:    RA = 23h 27m 07s, Dec = +6o 21' 50" (J2000).

Ground analysis of the SXC data for the burst also produced a refined 
location, which was reported in a GCN Position Notice issued 176 
minutes after the burst.  The SXC location can be expressed as a 90% 
confidence circle that is 130 arcseconds in radius and is centered at

SXC:    RA = 23h 27m 24s, Dec = +6o 16' 08" (J2000).

We note that the SXC error circle (reported at 17:54:08 UTC) lies 
almost fully within the subsequently-reported IPN annulus (Hurley et 
al, GCN1507
Not found
 
 
, issued at 19:30:40 UTC). Also, the catalogued X-ray 
source 1RXS J232705.9+062419 lies within the WXM error box, but is 
not within the SXC error box.

Further information (including a light curve and the error boxes) for 
GRB020819 is provided at the following URL:

http://space.mit.edu/HETE/Bursts/

This message is citable.