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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"

19023 results found.

  1. SGR 1900+14: Detection of extended X-ray emission
  2. Chandra Observations of SGR 1900+14
  3. SGR 1900+14, Chandra observations
  4. Chandra Observations of SGR 1900+14
  5. SGR1900+14, I-band observations
  6. SGR 1806-20 burst activity
  7. BATSE GRB trigger criteria
  8. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  9. GRB990308 not a new SGR
  10. GRB990308, Possible new SGR~0209+70
  11. SGR1900+14, BeppoSAX-GRBM observations
  12. SGR1627-41
  13. SGR1627-41, RXTE/ASM observations
  14. Reduced error box of SGR 1627-41
  15. SGR 1627-41
  16. Discovery of a new SGR source, SGR1627-41
  17. SGR 1900+14
  18. SGR1900+14
  19. SGR1900+14
  20. BATSE on-board GRB trigger change
  21. IRAS 18119-1342 and the possible new SGR
  22. Possible new SGR from US Naval Observatory
  23. RXTE Observations of SGR 1814-13

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