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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 250823A: Swift-BAT refined analysis
  2. GRB 250823A: Swift-XRT refined Analysis
  3. GRB 250823A: COLIBRÍ optical observations
  4. GRB 250823A: SVOM/VT optical observation
  5. GRB 250823A: Swift/UVOT Detection
  6. GRB 250823A: NOT optical observations
  7. GRB 250823A: Fermi GBM Observation
  8. GRB 250823A: Enhanced Swift-XRT position
  9. GRB 250823A: LCOGT Optical Detection
  10. GRB 250823A: BOOTES6/DPRT early optical detection
  11. GRB 250823A: Liverpool Telescope optical detection
  12. GRB 250823A: Swift detection of a burst
  13. GRB 250823A: Fermi GBM Final Real-time Localization

Advanced

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