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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"

36292 results found.

  1. GRB 991208 optical observations
  2. GRB 991208 optical observations
  3. GRB 991208: Radio Observations
  4. IPN localization of GRB991208
  5. Optical Observations of GRB991105
  6. GRB991106: BeppoSAX/BATSE results
  7. GRB 991106, optical observations
  8. GRB991106, near-infrared observations
  9. BeppoSAX NFI Observation of GRB991106
  10. GRB 991106, radio observations
  11. GRB991106: the first BeppoSAX short GRB detection?
  12. GRB 991105: BATSE Observations
  13. IPN localization of GRB991105
  14. GRB 991106 Optical Observations
  15. GRB 991105, optical observations
  16. GRB991106, optical observation at SAO-RAS
  17. GRB 991106, LOTIS Optical Observations
  18. GRB 991106, optical observations
  19. BeppoSAX GRB Alert: GRB991106
  20. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  21. GRB ALERT: GRB991105
  22. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  23. GRB 991014, Optical Observations
  24. GRB 991014 - BeppoSAX NFI observations
  25. GRB 991014, Optical Observations
  26. GRB 991014, radio observations
  27. GRB991014 BATSE Observations
  28. GRB 991014, Optical Observations
  29. GRB 991014, optical observations
  30. Super-LOTIS optical observation of GRB991014
  31. IPN/NFI error box for GRB991014
  32. IPN localization of GRB991014 - CORRECTION
  33. IPN localization of GRB991014
  34. BeppoSAX ALERT: GRB991014
  35. GRB 990915 optical observations
  36. GRB 990907 optical observations
  37. BATSE GRB trigger criteria
  38. Optical Observations of GRB990907
  39. IPN error box for GRB990915 (=BATSE 7766)
  40. IPN localization of BATSE #7766 (GRB990915)
  41. IPN localization of GRB990907
  42. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  43. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  44. GRB 990712 Late Optical Decay and Host Galaxy
  45. GRB 990712, Optical Observation
  46. GRB990806: BATSE Observations
  47. GRB 990806 Optical observations
  48. Optical Observations of GRB990806
  49. GRB 990806, Optical Observations
  50. GRB 990806, optical observations
  51. GRB 990806, Optical Observations
  52. GRB990806 UBVRIJHK observations
  53. GRB990806: possible X-ray afterglow, BeppoSAX
  54. BeppoSAX ALERT GRB990806: Summer GRB
  55. GRB 990712 Optical Observations
  56. GRB990705: No Evidence for Neutrino Signal
  57. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  58. VLT spectrum of GRB990712
  59. GRB 990712
  60. Late-time HST/STIS Observations of GRB 990510
  61. Refined BeppoSAX-WFC position of GRB990712
  62. GRB 990705, R-band observations
  63. Updated IPN localization of GRB990705
  64. IPN localization of GRB990704
  65. IPN localization of GRB990705
  66. Infrared and Optical Observations of GRB990705
  67. GRB 990705, radio observations
  68. GRB990704 radio and optical observations
  69. BeppoSAX GRB990705: possible X-ray afterglow
  70. GRB 990704 X-ray Observations
  71. GRB 990704 Optical Observations
  72. GRB 990704, optical observations
  73. GRB990704
  74. GRB990705: Intriguing Positional Coincidences
  75. GRB990704
  76. GRB990704, optical observations
  77. GRB990704: possible X-ray afterglow
  78. Identification of a possible optical counterpart for GRB990704
  79. GRB990704
  80. Refined BeppoSAX-WFC position of GRB990704
  81. GRB990704: BeppoSAX detection
  82. Optical Observations of GRB990627
  83. GRB 990627, radio observations
  84. GRB990627: BeppoSAX-WFC final location
  85. BeppoSAX: GRB990625
  86. Late-time HST/STIS Observation of GRB 990123
  87. GRB 990506 - clarification to GCN 352
  88. GRB 990506 - Optical Observations
  89. Optical Observations of GRB 990506
  90. GRB 990506 Radio Transient
  91. GRB990527 Optical Observations
  92. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  93. IPN error box for GRB990527
  94. Late Afterglows of GRBs 990510, 990123
  95. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  96. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  97. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  98. GRB 990506 optical observation
  99. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  100. X-ray/GRB 1SAX J0835.9+5118, Optical Observation

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