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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 230217A: ATCA rapid-response radio detection
  2. GRB 230217A: VLT/FORS2 optical observations and candidate counterpart
  3. GRB 230217A: Swift/UVOT Upper Limits
  4. GRB 230217A: Continued Gemini Observations
  5. GRB 230217A: Swift-XRT afterglow detection
  6. GRB 230217A: Swift-BAT refined analysis
  7. GRB 230217A: AstroSat CZTI detection
  8. GRB 230217A: Gemini South optical upper limits
  9. GRB 230217A: 6 GHz VLA observations
  10. GRB 230217A: Gemini-South Optical Observation
  11. IceCube-230217A: Upper limits from a search for additional neutrino events in IceCube
  12. GRB 230217A: Fermi GBM observation
  13. IceCube-230217A: BOOTES-4/MET Optical Observations
  14. Fermi-LAT gamma-ray observations of IceCube-230217A
  15. Konus-Wind detection of GRB 230217A
  16. GRB 230217A: Swift-XRT observations
  17. GRB 230217A: AGILE/MCAL detection
  18. GRB 230217A: Swift detection of a short burst
  19. GRB 230217A: Fermi GBM Final Real-time Localization
  20. IceCube-230217A - IceCube observation of a high-energy neutrino candidate track-like event

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Download all Circulars as a .tar.gz archive:
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