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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23 results found.

  1. GRB 240809A: Mondy and AbAO Optical Observations
  2. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  3. GRB 240809A: Correction to the VLA source position in GCN 37158
  4. GRB 240809A: ATA radio non-detection
  5. GRB 240809A : RAPAS follow-up observations
  6. GRB 240809A: VLA detection
  7. GRB 240809A: ALMA detection
  8. GRB 240809A: Swift-BAT refined analysis
  9. Konus-Wind detection of GRB 240809A
  10. GRB 240809A: REM detection of the optical afterglow
  11. GRB 240809A: Bassano Bresciano Observatory optical observations
  12. GRB 240809A: Conclusive redshift from VLT
  13. GRB 240809A: KAIT optical observations
  14. GRB 240809A: GIT afterglow observations
  15. GRB 240809A: Swift/UVOT Detection
  16. GRB 240809A: Tentative redshift from NOT
  17. GRB 240809A: Swift-XRT refined Analysis
  18. Swift GRB 240809A: Global MASTER-Net observations report
  19. GRB 240809A: JinShan optical observations
  20. GRB 240809A: Enhanced Swift-XRT position
  21. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  22. GRB 240809A: SVOM/GRM observation
  23. GRB 240809A: Swift detection of a burst with a bright optical counterpart

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Download all Circulars as a .tar.gz archive:
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