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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"

13 results found.

  1. GRB 250911A: MAXI/GSC detection
  2. Konus-Wind detection of GRB 250911A
  3. GRB 250911A: Insight-HXMT detection
  4. IceCube-Cascade 250911A: Upper limits from a search for additional neutrino events in IceCube
  5. GRB 250911A: GECAM-B detection
  6. GRB 250911A: Swift-BAT refined analysis
  7. GRB 250911A: MASTER optical counterpart observations
  8. GRB 250911A: Swift-XRT refined Analysis
  9. GRB 250911A: Swift/UVOT Detection
  10. GRB 250911A: Enhanced Swift-XRT position
  11. GRB 250911A: Swift-XRT observations
  12. GRB 250911A: COLIBRÍ optical counterpart candidate
  13. GRB 250911A: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

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