[vsnet-grb-info 15482] GRB 140903A: Swift-BAT Spectral lag analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16771
SUBJECT: GRB 140903A: Swift-BAT Spectral lag analysis
DATE:    14/09/04 06:32:31 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

T. Sakamoto (AGU), J. Norris (BSU), S. D. Barthelmy (GSFC), 
N. Gehrels (GSFC) report:

We report the spectral lag analysis for GRB 140903A (GCN Circ. 16764 & 16765) 
based on the BAT data.  Using 4-ms binned light curve, the spectral lag for 
the 50-100 keV to 100-350 keV bands is 16 +- 7 ms, and 21 +- 7 ms for the 15-25 keV 
to 50-100 keV bands.  There is no evidence for extended emission.  Those lag values 
are consistent with the short end of the long-burst lag distribution.  Although the 
lag analysis suggests GRB 140903A is consistent with a long GRB population, a further 
observation is needed to understand the nature of this burst.