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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"

3 results found.

  1. GRB 240129A: further SAO RAS optical observations
  2. GRB 240129A: Fermi GBM Observation
  3. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV

Advanced

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