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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"

2623 results found.

  1. GRB 990123: Bright New Source, Possible Optical Transient
  2. Possible identification of SN1999E with GRB980910
  3. GRB981220
  4. GRB 981226 optical observations
  5. GRB 981220
  6. GRB980703: Radio transient
  7. SGR1627-41, Refined IPN annulus location
  8. Reduced error box of SGR 1627-41
  9. SGR 1627-41
  10. SGR1900+14
  11. SGR1900+14
  12. GRB980519 optical observations
  13. GRB980519 Optical Observations
  14. GRB 980425 Brightness Temperature
  15. GRB980329 infrared observations
  16. Optical Observations of the GRB 971227 field
  17. GRB971227: Plaskett R-band observations
  18. GRB 971227: Optical clarifications
  19. GRB 971214: Redshift from Keck Optical Observations
  20. GRB 971214: USNOFS Observations Summary
  21. IRAS 18119-1342 and the possible new SGR
  22. Possible new SGR from US Naval Observatory
  23. GRB 970828: Palomar Observations

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