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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 060121 : pseudo-z = 1.9 ('intermediate-duration' burst)
  2. GRB 060121: HST observations
  3. GRB 060121 : WIDGET Pre-trigger limit
  4. GRB 060121: Gemini Late-time Observations
  5. GRB 060121: Confirmation of NIR Afterglow
  6. GRB 060121: Probable Detection of NIR Afterglow
  7. GRB 060121: OHP optical limits
  8. GRB 060121: Swift/UVOT upper limits
  9. GRB 060121: Liverpool Telescopes optical limits
  10. GRB 060121: Swift XRT refined analysis
  11. Konus-Wind observation of GRB 060121
  12. GRB 060121: I-band Limits
  13. GRB 060121: Confirmation of Afterglow
  14. GRB 060121: candidate optical counterpart
  15. GRB 060121: Swift XRT refined position
  16. GRB 060121: optical observations
  17. GRB 060121: Infrared Observations
  18. GRB 060121: optical observations
  19. GRB 060121: Optical imaging
  20. GRB 060121: A short-hard GRB in a cluster?
  21. GRB 060121 (=H4010): Results of preliminary spectral analysis
  22. GRB 060121: A bright short/hard GRB localized by HETE-2 SXC
  23. GRB 060121: A bright short/hard GRB localized by HETE-2 WXM

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Download all Circulars as a .tar.gz archive:
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