TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4372
SUBJECT: GRB 051221: Possible nearby cluster
DATE:    05/12/21 09:26:41 GMT
FROM:    Edo Berger at Carnegie Obs  <eberger@ociw.edu>

E. Berger (Carnegie Observatories) reports:
 
"Further examination of the Gemini data reveals a clustering of faint
galaxies extending about 1.5' eastward from the position of the X-ray
afterglow (GCN 4366) and the optical/near-IR source possibly associated
with the burst (GCNs 4367-9):
        http://www.ociw.edu/~eberger/grb051221-gemini.tif
 
Additional multi-band photometry and an analysis of spatial clustering are
required in order to verify whether this is a true galaxy cluster and
whether the optical/near-IR source is related to this possible structure.  
This analysis is in progress."