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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"

7 results found.

  1. GRB050801: GCN XRT position is incorrect
  2. GRB 050701
  3. GRB 050701, optical observations
  4. GRB 050701: Refined XRT analysis
  5. Swift UVOT observations of GRB 050701
  6. GRB 050701: Swift XRT afterglow position
  7. Swift trigger 143708 is really GRB 050701

Advanced

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