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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"

3867 results found.

  1. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  2. GRB 000326: Optical Observations
  3. GRB 000301C, Optical Observation
  4. GRB000301C
  5. GRB 000301C : Optical Candidate
  6. GRB000226 [IPN Position]
  7. HST Observations of GRB 990712
  8. IPN annulus for GRB000214
  9. GRB000126, optical observations
  10. IPN localization of GRB000126
  11. GRB991216 late optical observation
  12. BEPPOSAX GRBM Localization of GRB991226
  13. IPN error boxes for GRB991229
  14. IPN localization of GRB991226
  15. IPN localization of GRB991208
  16. IPN localization of GRB991014 - CORRECTION
  17. IPN localization of GRB991014
  18. BATSE GRB trigger criteria
  19. GRB 990712 Late Optical Decay and Host Galaxy
  20. GRB 990712, Optical Observation
  21. GRB 990712
  22. IPN localization of GRB990705
  23. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  24. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  25. GRB 990510: optical observations
  26. GRB 990510: optical observations
  27. GRB990510: X-ray afterglow
  28. GRB 990510: optical observation
  29. GRB 990510: Broad Band Break
  30. GRB990510: optical observation
  31. GRB 990510 Optical Observations
  32. GRB 990510 optical observations
  33. GRB990510 optical observations
  34. GRB990510
  35. GRB 990510 optical observations
  36. GRB 990510 optical observations
  37. GRB 990510 optical observations
  38. IPN localization of GRB990510
  39. New IPN/RXTE error box for GRB990506
  40. GRB990308 not a new SGR
  41. GRB990308, Possible new SGR~0209+70
  42. GRB 990123: Discovery of the Probable Host Galaxy
  43. Possible identification of SN1999E with GRB980910
  44. GRB 981226: radio variable
  45. GRB 981226 Optical Observations
  46. GRB981226, sub-millimeter observations
  47. GRB 981226
  48. GRB 981226 optical observations
  49. Optical Observations of GRB981226
  50. GRB 981226 - Infrared Observations
  51. SGR1900+14, BeppoSAX-GRBM observations
  52. SGR1627-41
  53. SGR1627-41, RXTE/ASM observations
  54. Reduced error box of SGR 1627-41
  55. SGR 1627-41
  56. Discovery of a new SGR source, SGR1627-41
  57. GRB980613 observations from Palomar
  58. SGR 1900+14
  59. SGR1900+14
  60. SGR1900+14
  61. BATSE on-board GRB trigger change
  62. GRB980329 IPN annulus
  63. Optical Observations of GRB 970508
  64. IRAS 18119-1342 and the possible new SGR
  65. Possible new SGR from US Naval Observatory
  66. RXTE Observations of SGR 1814-13
  67. GRB 970828: Palomar Observations

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