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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"

10 results found.

  1. GRB 221027B: GRANDMA observations
  2. GRB 221027B: Swift-BAT refined analysis
  3. GRB 221027B: COATLI Upper Limits
  4. GRB 221027B: Swift/UVOT Upper Limits
  5. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  6. Swift GRB 221027B: Global MASTER-Net observations report
  7. GRB 221027B: Swift-XRT refined Analysis
  8. GRB 221027B: BOOTES-1 optical upper limit
  9. GRB 221027B: Enhanced Swift-XRT position
  10. GRB 221027B: Swift detection of a burst

Advanced

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