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GCN Circular 11836

GRB 110328A / Swift J164449.3+573451: EVLA Detection
2011-03-29T21:50:24Z (13 years ago)
Ashley Zauderer at CfA <>
Ashley Zauderer, Edo Berger (Harvard), Dale A. Frail (NRAO) and Alicia 
Soderberg (Harvard) report on behalf of a larger collaboration:

We observed the peculiar Swift event GRB110328A / Swift J164449.3+573451 
(GCNs 11823, 11824) with the EVLA on March 29.37 UT at two frequencies 
(1 GHz bandwidth each) centered at 4.94 and 6.69 GHz.   We find a 
single, unresolved >10 sigma radio source within the Swift-XRT error 
circle (GCN 11826) at the following position (J2000):

RA =  16:44:49.93,
DEC = +57:34:59.7

coincident with the PTF and NOT optical source (GCNs 11827 and 11830). 
The optical source showed no clear variability in brightness and is thus 
most likely the host galaxy of this event, with a redshift of z=0.35 
(GCNs 11833, 11834).  The EVLA source is most likely the radio afterglow 
of this peculiar burst.

Further observations are planned.
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