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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"

2847 results found.

  1. GRB 021004: Optical observations at RIKEN
  2. GRB 021004: Optical Observations
  3. GRB 021004: Optical Observations
  4. GRB 021004, SPM optical observations
  5. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  6. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time
  7. IPN triangulation of GRB020708
  8. IPN triangulation of GRB020708
  9. GRB 020625, optical observations
  10. GRB 020317 : KISO Optical Observations
  11. GRB 020305: Candidate optical afterglow
  12. GRB020305, optical observations
  13. GRB020305 (=H1939): Localization of a GRB by HETE
  14. IPN Upper Limits to a GRB Associated With SN2002ap
  15. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  16. GRB 011130: Optical Observations of Chandra Sources
  17. GRB011130 (XRF011130) Chandra Observations
  18. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  19. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  20. SGR1806-20: Localization by HETE
  21. GRB010222: possible optical counterpart
  22. IPN triangulation of GRB 001004
  23. GRB000926 K'-band Observation
  24. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  25. IPN localization of GRB000801
  26. IPN localization of GRB000730
  27. GRB000623
  28. GRB000615, R-band photometry
  29. BeppoSAX X-ray transient/possible GRB000608
  30. GRB 000408, optical observations
  31. IPN annulus for GRB000115
  32. Single IPN error box for GRB991229
  33. IPN error boxes for GRB991229
  34. Single IPN error box for GRB991221
  35. IPN error boxes for GRB991221
  36. GRB 991216 RXTE ASM Observations
  37. IPN localization of GRB990704
  38. GRB990510: X-ray afterglow
  39. GRB990510 optical observations
  40. GRB 990506, optical observations
  41. GRB 990506, optical observations
  42. GRB 981220 Optical observations
  43. GRB981226, sub-millimeter observations
  44. Optical Observations of GRB981226
  45. GRB 981220:Optical Observations
  46. GRB 981226 - Infrared Observations
  47. GRB 971214: USNOFS Observations Summary

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