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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"

20 results found.

  1. GRB 210222B: TAROT Reunion observatory optical light curve
  2. GRB 210222B: 1.3m DFOT Optical upper limit
  3. GRB 210222B: REM observations of the optical/NIR afterglow
  4. GRB 210222B: MITSuME Akeno optical upper limits
  5. GRB 210222B: Zeiss-1000 of Koshka observatory, optical observations
  6. GRB 210222B: VIRT optical detection
  7. GRB 210222B: Swift-BAT refined analysis
  8. GRB 210222B: Swift-XRT refined Analysis
  9. GRB 210222B: Swift/UVOT Detection
  10. GRB 210222B: KAIT Optical Upper Limit
  11. GRB 210222B: FRAM-ORM afterglow detection
  12. GRB 210222B: MASTER OT observation
  13. GRB 210222B: Redshift from FORS2/VLT
  14. GRB 210222B: NEXT early optical afterglow observations
  15. GRB 210222B: GOTO confirmation of afterglow detection (correction to GCN29548)
  16. GRB 210222B: Liverpool Telescope optical detection
  17. GRB 210222B: GOTO confirmation of afterglow detection
  18. GRB210222B: LCO Optical Afterglow Detection
  19. GRB210222B: BOOTES-1 optical afterglow detection
  20. GRB 210222B: 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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