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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 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  2. GRB 231111A: Swift/UVOT Detection
  3. GRB 231111A: Swift-BAT refined analysis
  4. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  5. GRB 231111A: Xinglong-2.16m optical observations
  6. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  7. GRB 231111A: TNG tentative redshift
  8. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  9. GRB 231111A: Leavitt Observatory optical observations
  10. GRB231111A: Optical follow-up observations with Mephisto
  11. GRB 231111A: GMG observation (correction)
  12. GRB 231111A: GMG observation upper limit
  13. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  14. GRB 231111A: Swift-XRT refined Analysis
  15. GRB 231111A: Mondy optical observations
  16. GRB 231111A: GECAM-C detection of a long burst (correction)
  17. GRB 231111A: Enhanced Swift-XRT position
  18. GRB 231111A: GECAM-C detection of a long burst
  19. GRB231111A: YAHPT Observations
  20. GRB231111A: GIT confirmation of the optical afterglow
  21. GRB 231111A: MASTER OT earlier detection
  22. GRB 231111A: Nanshan/HMT optical observations
  23. GRB 231111A: Swift detection of a burst with an optical counterpart

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Download all Circulars as a .tar.gz archive:
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