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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

5 results found.

  1. GRB 090306B: Confirmation of the X-ray afterglow
  2. GRB 090306B: INTEGRAL SPI-ACS light curve
  3. GRB 090306B: GROND Upper Limits
  4. GRB 090306B: Possible XRT afterglow
  5. GRB 090306B: Burst detection from Swift-BAT slew data

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