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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"

3137 results found.

  1. GRB 020305: Candidate optical afterglow
  2. GRB020305, optical observations
  3. GRB020305 (=H1939): Localization of a GRB by HETE
  4. IPN Upper Limits to a GRB Associated With SN2002ap
  5. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  6. GRB 011130: Optical Observations of Chandra Sources
  7. GRB011130 (XRF011130) Chandra Observations
  8. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  9. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  10. SGR1806-20: Localization by HETE
  11. GRB010222: possible optical counterpart
  12. IPN triangulation of GRB 001004
  13. GRB000926 K'-band Observation
  14. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  15. IPN localization of GRB000801
  16. IPN localization of GRB000730
  17. GRB000623
  18. GRB000615, R-band photometry
  19. BeppoSAX X-ray transient/possible GRB000608
  20. GRB 000408, optical observations
  21. IPN annulus for GRB000115
  22. Single IPN error box for GRB991229
  23. IPN error boxes for GRB991229
  24. Single IPN error box for GRB991221
  25. IPN error boxes for GRB991221
  26. GRB 991216 RXTE ASM Observations
  27. IPN localization of GRB990704
  28. GRB990510: X-ray afterglow
  29. GRB990510 optical observations
  30. GRB 990506, optical observations
  31. GRB 990506, optical observations
  32. GRB 981220 Optical observations
  33. GRB981226, sub-millimeter observations
  34. Optical Observations of GRB981226
  35. GRB 981220:Optical Observations
  36. GRB 981226 - Infrared Observations
  37. GRB 971214: USNOFS Observations Summary

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