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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"

19 results found.

  1. GRB 250706A: Swift-BAT refined analysis
  2. IceCube-250706A: No Candidates from WINTER
  3. IceCube-250706A: No Candidates from the Zwicky Transient Facility
  4. IceCube-250706A: Upper limits from a search for additional neutrino events in IceCube
  5. IceCube-250706A: EP-FXT follow-up observations
  6. Fermi-LAT Gamma-ray Observations of IceCube-250706A
  7. IceCube-250706A: Global MASTER-Net observations report
  8. GRB 250706A: Swift-XRT refined Analysis
  9. GRB 250706A: Swift/UVOT Upper Limits
  10. GRB 250706A: REM optical/NIR observations
  11. EP250706a/GRB 250706A: EP-WXT detection of a fast X-ray transient
  12. IceCube-250706A: COLIBRÍ optical upper limits
  13. Swift GRB 250706A: Global MASTER-Net observations report
  14. GRB 250706A: JinShan optical upper limits
  15. GRB 250706A: SAO RAS optical observations
  16. GRB 250706A: SVOM/C-GFT upper limit in eary phase
  17. IceCube-250706A - IceCube observation of a high-energy neutrino candidate track-like event
  18. GRB 250706A: GROWTH-India Telescope optical upper limit
  19. GRB 250706A: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive:
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