[vsnet-grb-info 14066] GRB 131024B: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15380
SUBJECT: GRB 131024B: Swift/UVOT Upper Limits
DATE:    13/10/25 14:20:06 GMT
FROM:    Margaret Chester at PSU  <chester at astro.psu.edu>

M. M. Chester (PSU) and H. A. Krimm (CRESST/GSFC/USRA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 131024B
121 s after the BAT trigger (Krimm et al., GCN Circ. 15371).
No optical afterglow consistent with the XRT position (Beardmore et 
al. GCN Circ. 15374) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the second 
finding chart (FC) exposure and subsequent exposures are given in 
the following table.  (The first finding chart in White was 
incomplete and is not included in the analysis.)

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

u_FC               278          528          246         >19.7
white              559         5579          413         >21.8
v                  609         5990          413         >20.6
b                  535         5374          228         >20.5
u                  278         6484          539         >20.3
w1                 658         6401          413         >20.4
m2                4558         6195          393         >20.9
w2                 585         5785          413         >21.3

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).
************************************************************************
Dr. Margaret Chester				
Swift Deputy Mission Director              U.S. Mail:	
The Pennsylvania State University          Swift Explorer Program
Department of Astronomy & Astrophysics     2582 Gateway Drive
Office:  (814) 865-7746                    State College, PA  16801
Cell:  (814) 359-9026                      FAX:  (814) 865-9100