[vsnet-grb-info 2540] GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4377
SUBJECT: GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
DATE:    05/12/21 22:25:49 GMT
FROM:    Don Lamb at U.Chicago  <lamb at oddjob.uchicago.edu>

GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral Lag

J. Norris, 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, K. Tanaka, 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, G. Pizzichini, and S. Gunasekera, 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:

We have performed an analysis of the spectral lag for GRB 051211A,
using FREGATE data in the 30-85 keV and 85-400 keV energy bands.  We
obtain a spectral lag of 0.000 +/- 0.024 seconds.  This result provides
strong additional evidence that GRB 051211A is a short burst [Norris,
J. P., Scargle, J. D., and Bonnell, J. T.  2001, in Gamma-Ray Bursts in
the Afterglow Era, ed. E. Costa, F. Frontera, and J. Hjorth (Berlin:
Springer), p. 40; and Norris, J. P., and Bonnell, J. T. 2005, ApJ,
submitted (see, e.g., Figure 3)].