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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"

37083 results found.

  1. GRB 991106, radio observations
  2. GRB991106: the first BeppoSAX short GRB detection?
  3. GRB 991105: BATSE Observations
  4. IPN localization of GRB991105
  5. GRB 991106 Optical Observations
  6. GRB 991105, optical observations
  7. GRB991106, optical observation at SAO-RAS
  8. GRB 991106, LOTIS Optical Observations
  9. GRB 991106, optical observations
  10. BeppoSAX GRB Alert: GRB991106
  11. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  12. GRB ALERT: GRB991105
  13. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  14. GRB 991014, Optical Observations
  15. GRB 991014 - BeppoSAX NFI observations
  16. GRB 991014, Optical Observations
  17. GRB 991014, radio observations
  18. GRB991014 BATSE Observations
  19. GRB 991014, Optical Observations
  20. GRB 991014, optical observations
  21. Super-LOTIS optical observation of GRB991014
  22. IPN/NFI error box for GRB991014
  23. IPN localization of GRB991014 - CORRECTION
  24. IPN localization of GRB991014
  25. BeppoSAX ALERT: GRB991014
  26. GRB 990915 optical observations
  27. GRB 990907 optical observations
  28. BATSE GRB trigger criteria
  29. Optical Observations of GRB990907
  30. IPN error box for GRB990915 (=BATSE 7766)
  31. IPN localization of BATSE #7766 (GRB990915)
  32. IPN localization of GRB990907
  33. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  34. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  35. GRB 990712 Late Optical Decay and Host Galaxy
  36. GRB 990712, Optical Observation
  37. GRB990806: BATSE Observations
  38. GRB 990806 Optical observations
  39. Optical Observations of GRB990806
  40. GRB 990806, Optical Observations
  41. GRB 990806, optical observations
  42. GRB 990806, Optical Observations
  43. GRB990806 UBVRIJHK observations
  44. GRB990806: possible X-ray afterglow, BeppoSAX
  45. BeppoSAX ALERT GRB990806: Summer GRB
  46. GRB 990712 Optical Observations
  47. GRB990705: No Evidence for Neutrino Signal
  48. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  49. VLT spectrum of GRB990712
  50. GRB 990712
  51. Late-time HST/STIS Observations of GRB 990510
  52. Refined BeppoSAX-WFC position of GRB990712
  53. GRB 990705, R-band observations
  54. Updated IPN localization of GRB990705
  55. IPN localization of GRB990704
  56. IPN localization of GRB990705
  57. Infrared and Optical Observations of GRB990705
  58. GRB 990705, radio observations
  59. GRB990704 radio and optical observations
  60. BeppoSAX GRB990705: possible X-ray afterglow
  61. GRB 990704 X-ray Observations
  62. GRB 990704 Optical Observations
  63. GRB 990704, optical observations
  64. GRB990704
  65. GRB990705: Intriguing Positional Coincidences
  66. GRB990704
  67. GRB990704, optical observations
  68. GRB990704: possible X-ray afterglow
  69. Identification of a possible optical counterpart for GRB990704
  70. GRB990704
  71. Refined BeppoSAX-WFC position of GRB990704
  72. GRB990704: BeppoSAX detection
  73. Optical Observations of GRB990627
  74. GRB 990627, radio observations
  75. GRB990627: BeppoSAX-WFC final location
  76. BeppoSAX: GRB990625
  77. Late-time HST/STIS Observation of GRB 990123
  78. GRB 990506 - clarification to GCN 352
  79. GRB 990506 - Optical Observations
  80. Optical Observations of GRB 990506
  81. GRB 990506 Radio Transient
  82. GRB990527 Optical Observations
  83. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  84. IPN error box for GRB990527
  85. Late Afterglows of GRBs 990510, 990123
  86. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  87. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  88. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  89. GRB 990506 optical observation
  90. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  91. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  92. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  93. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  94. radio observations of X-ray/GRB transient field
  95. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  96. Optical report on X-ray/GRB transient
  97. radio detection of X-ray/GRB transient
  98. BeppoSAX: A new fast X-ray transient
  99. GRB 990510: optical observations
  100. GRB990510: photometric and spectroscopic observations with the VLT

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