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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').

3 results found.

  1. GRB 231203A: Fermi GBM Observation
  2. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  3. GRB 231203A: Fermi GBM Final Real-time Localization

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