TITLE: GCN CIRCULAR NUMBER: 11848 SUBJECT: GRB 110328A / Swift J164449.3+573451: EVLA observations of a brightening radio source DATE: 11/03/30 23:07:49 GMT FROM: Edo Berger at Harvard Ashley Zauderer, Edo Berger (Harvard), Dale A. Frail (NRAO) and Alicia Soderberg (Harvard) report: "We re-observed the peculiar Swift event GRB110328A / Swift J164449.3+573451 (GCNs 11823, 11824) with the EVLA on March 30.49 UT. At the two frequenciescentered at 4.94 and 6.69 GHz we find that the previously-detected radio source (GCN 11836) has significantly brightened (~10-sigma confidence level). This provides the first clear evidence connecting the quiescent optical source at z=0.35 (GCNs 11827, 11830, 11833, 11834), which is positionally coincident with the brightening radio source, and the transient X-ray/gamma-ray source (which is localized to only 1.7" radius accuracy; GCN 11826)."