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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"

18616 results found.

  1. GRB041223: Swift-BAT detection of a bright long burst
  2. GRB041220: Swift-BAT burst
  3. GRB 041219 Optical Observations
  4. GRB041219c: Third Burst in One Day from Swift-BAT
  5. GRB041219b: A Swift-BAT burst
  6. Swift-BAT detection of the bright long burst GRB041219
  7. GRB041217: optical limit 30 min after GRB
  8. GRB041217: Optical Observations
  9. GRB041217: NIR and optical observations with REM
  10. GRB041217: P60 Optical Observations
  11. GRB041217: Infrared Observations
  12. GRB041217: The First GRB Located On-Board Swift
  13. GRB040916: Optical observations
  14. GRB040422: optical and NIR observations at the VLT
  15. GRB040223, improved XMM position
  16. SN 2003jd (SN/GRB?) - possible association with GRB 030929

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