[AAVSO-HEN] GRB 080319B: Further HST observations and underlying host

[grb at aavso.org]

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TITLE:   GCN CIRCULAR
NUMBER:  7710
SUBJECT: GRB 080319B: Further HST observations and underlying host
DATE:    08/05/12 18:35:30 GMT
FROM:    Andrew Levan at U.of Leicester  <anl at star.le.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester), A.S. Fruchter (STScI) 
and J. Graham (STScI) report:

We have obtained a second epoch of HST observations of GRB 080319B on 11 
May 2008. 2 orbits (3200s) of observations were taken in the F606W and 
F814W filters. The afterglow has clearly faded from our first epoch of 
observations and a faint host galaxy is now visible at the afterglow 
location. We measure magnitudes for the combined (afterglow+host) source 
of;

F606W(AB)=26.3 +/ -0.1
F814W(AB)=25.9 +/ -0.1

Relative astrometry between the two epochs of HST observations suggests 
that the afterglow is marginally (0.1 +/- 0.05 arcseconds) offset from the 
centroid of the host galaxy in the F606W image. This implies that the 
afterglow may not be the dominant source of light at the current epoch, 
and is likely significantly fainter than the magnitudes quoted above.