TITLE:   GCN CIRCULAR
NUMBER:  4146
SUBJECT: GRB051021b: Magellan IR Imaging
DATE:    05/10/23 05:45:47 GMT
FROM:    Josh Bloom at UC Berkeley  <jbloom@astron.berkeley.edu>

D. L. Kaplan (MIT), H-W. Chen (Chicago), J. S. Bloom (UCB), J. X.  
Prochaska (UCO LIck) report on behalf of a large collaboration:

"We obtained deep K-band imaging of the field of GRB 051021b (GCN  
4135) with PANIC on the Magellan Baade Telescope starting at 08:42:56  
October 22, 2005 UTC. We identify 4 sources within the XRT error  
circle (GCN 4128):

   08:24:11.803 -45:32:30.79 J2000
   08:24:11.598 -45:32:31.93 J2000
   08:24:11.622 -45:32:33.70 J2000
   08:24:11.724 -45:32:34.20 J2000

The 1 sigma uncertainty relative to 2MASS is 300 mas.  As all of  
these sources are significantly fainter than the 2MASS detection  
limit we cannot identify an obvious afterglow candidate."

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