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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"

5 results found.

  1. GRB 240914A: Swift-XRT observations
  2. GRB 240914A: SVOM/GRM observation
  3. GRB 240914A: Swift ToO observations
  4. GRB 240914A: ESO-NTT optical observations
  5. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.

Advanced

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