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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 231123C: Fermi GBM Observation
  2. GRB 231123C: Insight-HXMT/HE detection
  3. GRB 231123C (short): Glowbug gamma-ray detection
  4. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  5. GRB 231123C: Fermi GBM Final Real-time Localization

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