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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"

4064 results found.

  1. GRB000301C
  2. GRB 000301C : Optical Candidate
  3. GRB000226 [IPN Position]
  4. HST Observations of GRB 990712
  5. IPN annulus for GRB000214
  6. GRB000126, optical observations
  7. IPN localization of GRB000126
  8. GRB991216 late optical observation
  9. BEPPOSAX GRBM Localization of GRB991226
  10. IPN error boxes for GRB991229
  11. IPN localization of GRB991226
  12. IPN localization of GRB991208
  13. IPN localization of GRB991014 - CORRECTION
  14. IPN localization of GRB991014
  15. BATSE GRB trigger criteria
  16. GRB 990712 Late Optical Decay and Host Galaxy
  17. GRB 990712, Optical Observation
  18. GRB 990712
  19. IPN localization of GRB990705
  20. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  21. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  22. GRB 990510: optical observations
  23. GRB 990510: optical observations
  24. GRB990510: X-ray afterglow
  25. GRB 990510: optical observation
  26. GRB 990510: Broad Band Break
  27. GRB990510: optical observation
  28. GRB 990510 Optical Observations
  29. GRB 990510 optical observations
  30. GRB990510 optical observations
  31. GRB990510
  32. GRB 990510 optical observations
  33. GRB 990510 optical observations
  34. GRB 990510 optical observations
  35. IPN localization of GRB990510
  36. New IPN/RXTE error box for GRB990506
  37. GRB990308 not a new SGR
  38. GRB990308, Possible new SGR~0209+70
  39. GRB 990123: Discovery of the Probable Host Galaxy
  40. Possible identification of SN1999E with GRB980910
  41. GRB 981226: radio variable
  42. GRB 981226 Optical Observations
  43. GRB981226, sub-millimeter observations
  44. GRB 981226
  45. GRB 981226 optical observations
  46. Optical Observations of GRB981226
  47. GRB 981226 - Infrared Observations
  48. SGR1900+14, BeppoSAX-GRBM observations
  49. SGR1627-41
  50. SGR1627-41, RXTE/ASM observations
  51. Reduced error box of SGR 1627-41
  52. SGR 1627-41
  53. Discovery of a new SGR source, SGR1627-41
  54. GRB980613 observations from Palomar
  55. SGR 1900+14
  56. SGR1900+14
  57. SGR1900+14
  58. BATSE on-board GRB trigger change
  59. GRB980329 IPN annulus
  60. Optical Observations of GRB 970508
  61. IRAS 18119-1342 and the possible new SGR
  62. Possible new SGR from US Naval Observatory
  63. RXTE Observations of SGR 1814-13
  64. GRB 970828: Palomar Observations

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