[AAVSO-HEN] GRB 090113: Swift UVOT upper limits

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TITLE:   GCN CIRCULAR
NUMBER:  8813
SUBJECT: GRB 090113: Swift UVOT upper limits
DATE:    09/01/14 13:39:14 GMT
FROM:    Samantha Oates at MSSL  <sro at mssl.ucl.ac.uk>

S. R. Oates (MSSL-UCL) 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 090113 79s after the BAT trigger (Krimm et al., GCN 8804).
We do not detect any source at the enhanced Swift XRT position
(Evans et al. GCN 8809). Due to trigger 339853 the automatic
target sequence was cut short and only the white and u finding charts  
were taken.
In the u finding chart and in the second orbit of data the XRT position
lies outside of the UVOT images. Therefore, we can only report the 3- 
sigma upper
limit for the white finding chart exposure.

The 3-sigma upper limits for the finding chart exposure is:

Filter   T_start   T_stop   Exp(s)  Mag (3-sigma upper limit)
-------------------------------------------------------------
white      79       229      147     > 20.73
-------------------------------------------------------------

The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.08 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).