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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

6 results found.

  1. GRID detection of GRB 240306A
  2. GRB 240306A: Fermi GBM observation
  3. GRB 240306A: AstroSat CZTI detection
  4. Fermi GRB 240306A: Global MASTER-Net observations report
  5. GRB 240306A: Swift/BAT-GUANO detection of a burst
  6. GRB 240306A: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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