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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').

4 results found.

  1. GRB 090720: Gemini-North Imaging and Optical Afterglow
  2. Swift XRT and UVOT refned analysis of GRB 090720
  3. GRB 090720 Source found in ground processing of Swift-BAT data
  4. GRB 090720: Fermi GBM detection

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