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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

22 results found.

  1. GRB 230430A: A short GRB from a neutron star merger
  2. GRB 210410A: A twin of short GRB 090510 with complementary observations
  3. Update to the configuration of the Fermi-LAT onboard GRB search
  4. GRB 090510: Suzaku WAM observation of the prompt emission
  5. GRB 090510, Radio limits
  6. GRB090510: VLT/FORS2 spectroscopic redshift
  7. GRB 090510: GROND observations
  8. GRB 090510: Swift/UVOT host galaxy candidates
  9. GRB 090510: Fermi-LAT follow-up analysis
  10. GRB 090510: correction to GCN 9344
  11. Konus-Wind observation of GRB 090510
  12. AGILE detection of GRB 090510
  13. GRB 090510: UVOT refined analysis
  14. GRB 090510: Swift XRT refined analysis
  15. GRB 090510: correction to coordinates in GCN 9338
  16. GRB 090510: Enhanced Swift-XRT position
  17. GRB 090510: NOT afterglow confirmation
  18. GRB 090510: Swift-BAT refined analysis
  19. GRB 090510: Fermi GBM detection
  20. Fermi LAT detection of GRB 090510
  21. GRB 090510: Swift/UVOT Detection of a Candidate Optical Afterglow
  22. GRB 090510: Swift detection of a short hard burst

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Download all Circulars as a .tar.gz archive:
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