TITLE:   GCN CIRCULAR
NUMBER:  3069
SUBJECT: GRB050215B: Late-Time Swift UVOT Observations
DATE:    05/03/03 20:17:31 GMT
FROM:    Pete Roming at PSU  <roming@astro.psu.edu>

P. Brown (PSU), S. Rosen, K. McGowan, M. De Pasquale (MSSL), P. Boyd 
(GSFC/UMBC), S. T. Holland, M. Still (GSFC/USRA), W. Landsman (GSFC), S. 
Hunsberger (PSU), A. Breeveld (MSSL), P. Roming (PSU), K. Mason, P. Schady 
(MSSL), M. Ivanushkina (PSU), T. Poole (MSSL), C. Gronwall (PSU), A. 
Blustin (MSSL), S. Koch (PSU), M. Carter, H. Huckle (MSSL),  P. Broos 
(PSU), T. Kennedy, P. Smith, B. Hancock (MSSL), M. Chester (PSU), B. Zhang 
(UNLV), J. Nousek (PSU), N. Gehrels (GSFC), on behalf of the Swift UVOT team.


The Swift Ultra-Violet/Optical Telescope (UVOT) observed the field of the 
X-ray flash GRB050215B (GCN 3024) between February 25, 2005 and February 
28, 2005 UT.  The 5-sigma limiting magnitudes for each exposure are 
presented below.  We stress that the limiting magnitudes are based on 
ground calibrations and are uncertain by approximately +/-0.5 mag.

#                       Exposure
#   Date (UTC) Time     Time (s)  Filter   Mag
  2005-02-25  15:13:13   1670.52     V     22.2
  2005-02-25  19:52:34   2189.47     B     23.0
  2005-02-25  21:32:35   2068.95     U     22.7
  2005-02-25  23:27:38    985.24     V     21.9
  2005-02-26  02:34:31   1351.94     V     22.0
  2005-02-27  15:20:04   2099.11     B     22.9
  2005-02-28  01:07:03   1620.44     V     22.2
  2005-02-28  10:40:04   1919.99     B     22.9

We find no evidence for a brightening source, such as a supernova 
component, at the location of the afterglow seen by UKIRT (GCN 3031).