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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').

6 results found.

  1. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  2. GRB 230709C: GRBAlpha detection
  3. GRB 230709C: Fermi GBM Detection
  4. GRB 230709C: Fermi GBM Final Localization
  5. GRB 230709C: AstroSat CZTI detection
  6. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)


Download all Circulars as a .tar.gz archive:
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