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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"

22 results found.

  1. GRB 251205A: Kilonova-Catcher optical afterglow detection
  2. GRB 251205A: 1.3m DFOT optical upper limit
  3. Fermi GBM Sub-Threshold Detection of GRB 251205A
  4. GRB 251205A: J-band detection with WINTER
  5. GRB 251205A: Liverpool Telescope further optical follow-up observations
  6. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  7. GRB 251205A: FTW optical and NIR observations
  8. GRB 251205A: Liverpool Telescope further optical follow-up observations
  9. GRB 251205A: ZTF and ATLAS optical afterglow detections
  10. GRB 251205A: GROWTH-India Telescope optical observations
  11. GRB 251205A: Swift-BAT refined analysis
  12. GRB 251205A: Swift-XRT refined Analysis
  13. GRB 251205A: Swift/UVOT Detection
  14. GRB 251205A: Liverpool Telescope optical follow-up observations
  15. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  16. GRB 251205A: COLIBRÍ optical observations
  17. GRB 251205A: GOTO optical afterglow detection
  18. GRB 251205A: NOT optical observations
  19. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  20. GRB 251205A: Enhanced Swift-XRT position
  21. Swift GRB 251205A : MASTER OT detection with host galaxy
  22. GRB 251205A: Swift detection of a burst with an optical afterglow

Advanced

Download all Circulars as a .tar.gz archive:
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