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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"

25 results found.

  1. GRB 170728B: Kottamia R-band observation
  2. GRB 170728B: 15 GHz upper limits from AMI
  3. GMRT upper limit on the radio afterglow of GRB 170728B
  4. GRB 170728B: TShAO, SAO RAS and AbAO optical observations
  5. GRB 170728B: time correction to MASTER GCN Circular 21391
  6. GRB 170728B: Swift/UVOT Further Analysis
  7. Konus-Wind observation of GRB 170728B
  8. GRB 170728B: VLA radio afterglow detection
  9. GRB 170728B: Optical observations at Crni Vrh
  10. GRB 170728B: BOOTES-2/TELMA optical detection during the extended gamma-ray phase
  11. GRB 170728B: MASTER-IAC first minute short GRB early OT detection
  12. GRB 170728B: COATLI Observations And Confirmation of Fading
  13. GRB 170728B: Swift/UVOT Upper Limits
  14. GRB 170728B iTelescope observation
  15. GRB 170728B, Swift-BAT refined analysis
  16. GRB 170728B: Fermi GBM detection
  17. GRB 170728B: I-band detection from 1.5m OSN
  18. GRB 170728B: Fermi-LAT detection
  19. GRB 170728B: Enhanced Swift-XRT position
  20. GRB 170728B: Swift-XRT refined Analysis
  21. GRB 170728B: LT afterglow confirmation
  22. GRB 170728B: NOT optical afterglow confirmation
  23. GRB 170728B: position of the TNG optical counterpart
  24. GRB 170728B: TNG optical afterglow candidate
  25. GRB 170728B: Swift detection of a short burst

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