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GCN Circular 32707

GRB 221009A/Swift J1913.1+1946: SMA observations
2022-10-12T18:54:52Z (2 years ago)
Lauren Rhodes at Oxford <>
Lauren Rhodes (University of Oxford), Kuiyun Huang (CYCU/PCCU) and Yvette Cendes (Harvard) report on behalf of a larger collaboration:

We observed the field of the candidate gamma-ray burst GRB 221009A (Swift J1913.1+1946; ATel#15650, ATel#15651) with the Submillimeter Array (SMA) at 230.7GHz beginning at 03:27UT on 12 October 2022 for a total of 3.3 hours. Uranus was used as the flux calibrator, while 3c84 was used to calibrate the bandpass response. 1925+211 and mwc349a were used as interleaved complex gain calibrators.

We detect an unresolved source at a position consistent with the UVOT position reported in ATel #15650 at a (preliminary) flux density of 9.30 +/- 0.75mJy. Further observations are planned.

We thank the staff at the SMA for carrying out these observations.
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