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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. GRB100504A: Optical upper limits at IAO
  2. GRB 100504A: Fermi GBM observation
  3. GRB 100504A: Swift/UVOT Observations
  4. GRB 100504A: Swift-XRT refined analysis
  5. GRB 100504A: Enhanced Swift-XRT position
  6. GRB 100504A: GROND Upper limits
  7. GRB 100504A: Swift-BAT refined analysis
  8. GRB 100504A: SARA-South Upper Limit
  9. GRB 100504A: UVOT-enhanced XRT position
  10. GRB 100504A: Swift detection of a burst

Advanced

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