TITLE:   GCN CIRCULAR
NUMBER:  7434
SUBJECT: GRB 080319b: Early IR Imaging from PAIRITEL
DATE:    08/03/19 08:30:12 GMT
FROM:    Josh Bloom at UC Berkeley  <jbloom@astron.berkeley.edu>

J. S. Bloom, D. Starr, and D. A. Perley (UC Berkeley) report:

We began observations of GRB080319b with PAIRITEL at 2008-03-19   
06:14:51 UT and will continue for several hours until sunrise. The  
source is exceedingly bright in the first few minutes, visible on  
individual 7.8 sec exposures in JHKs bands. Preliminary photometry,  
which may be affected to non-linearities at these bright flux levels,  
is given below.

# t (MJD)       terr (day)      filt     mag     merr
#####################################

54544.262141    0.000454        k       8.613900         
0.033214        0       0
54544.261788    0.000454        j       9.110600         
0.041347        0       0

A comparison with 2MASS may be found at:
    http://lyra.berkeley.edu/~jbloom/grb080319b.png

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