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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"

22 results found.

  1. GRB 111225A: Archeological redshift of the Christmas Burst 2011 from GTC
  2. GRB 111225A: optical observations
  3. GRB 111225A, the review of the sky area in plate archives
  4. GRB111225A: RAPTOR Early Detection of the Optical Counterpart
  5. GRB 111225A: optical observations in CrAO
  6. GRB 111225A: Lightbuckets Optical Observations
  7. GRB111228A: MITSuME Okayama Optical Observation
  8. GRB 111225A, optical observations
  9. GRB 111225A: Swift/UVOT Observations
  10. GRB 111225A: Keck/LRIS Afterglow Photometry
  11. GRB 111225A: PAIRITEL NIR Upper Limits
  12. GRB111225A: MITSuME Okayama optical upper limits
  13. GRB 111225A: GRT Optical Observation
  14. GRB 111225A: 1.23m CAHA optical observations
  15. GRB 111225A: Swift-XRT refined Analysis
  16. GRB 111225A, Swift-BAT refined analysis
  17. GRBv111225A: Xinglong TNT optical afterglow
  18. GRB 111225A: Enhanced Swift-XRT position
  19. GRB 111225A: Super-LOTIS early detection
  20. GRB 111225A: TAROT Calern observatory optical detection
  21. GRB 111225A: TAROT Calern observatory optical observations
  22. GRB 111225A: Swift detection of a burst with an optical counterpart

Advanced

Download all Circulars as a .tar.gz archive:
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