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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"

26 results found.

  1. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  2. GRB 170714A: NOEMA non-detection of the Bastille Day Burst
  3. GRB 170714A: Bastille Day Burst: ULGRB or RTDE?
  4. GRB 130925A: continuing Swift/XRT monitoring
  5. Konus-Wind observation of GRB 130925A
  6. GRB111209A: ATCA detection at 5.5, 9, and 18GHz
  7. GRB 111209A: RAPTOR Limits Before and During the Gamma-ray Emitting Interval
  8. GRB 111209A - ATCA 34GHz upper limit
  9. Konus-Wind observation of GRB 111209A
  10. GRB 111209A: Rebrightening seen by GROND
  11. GRB 111209A: IRTF NIR Imaging/Spectroscopy
  12. GRB 111209A: VLT/X-shooter redshift
  13. GRB 111209A: GROND Afterglow observations
  14. GRB 111209A optical limit by "Pi of the Sky"
  15. GRB 111209A: PROMPT optical observations of early afterglow
  16. GRB 111209A: Swift-XRT refined Analysis
  17. GRB 111209A: Swift UVOT refined analysis
  18. GRB 111209A: Swift Burst of Interest
  19. GRB 111209A, Swift-BAT refined analysis
  20. GRB 111209A: Enhanced Swift-XRT position
  21. GRB111209A : planned XMM-Newton observation
  22. GRB 111209A: TAROT La Silla observatory optical light curve analysis
  23. GRB 111209A: Faulkes Telescope North observations
  24. GRB 111209A: REM NIR detection
  25. GRB 111209A: TAROT La Silla observatory optical detection
  26. GRB 111209A: Swift detection of a long burst with an optical counterpart

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Download all Circulars as a .tar.gz archive:
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