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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"

41606 results found.

  1. GRB 991208 optical observations
  2. GRB 991208 optical observations
  3. GRB 991208: Radio Observations
  4. Optical Observations of GRB991105
  5. GRB991106: BeppoSAX/BATSE results
  6. GRB 991106, optical observations
  7. GRB991106, near-infrared observations
  8. BeppoSAX NFI Observation of GRB991106
  9. GRB 991106, radio observations
  10. GRB991106: the first BeppoSAX short GRB detection?
  11. GRB 991105: BATSE Observations
  12. GRB 991106 Optical Observations
  13. GRB 991105, optical observations
  14. GRB991106, optical observation at SAO-RAS
  15. GRB 991106, LOTIS Optical Observations
  16. GRB 991106, optical observations
  17. BeppoSAX refined position for GRB991106
  18. BeppoSAX GRB Alert: GRB991106
  19. Revised BeppoSAX WFC position of GRB991105
  20. GRB991105: SAX-GRBM/-WFC detection
  21. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  22. GRB ALERT: GRB991105
  23. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  24. GRB 991014, Optical Observations
  25. GRB 991014 - BeppoSAX NFI observations
  26. GRB 991014, Optical Observations
  27. GRB 991014, radio observations
  28. GRB991014 BATSE Observations
  29. GRB 991014, Optical Observations
  30. GRB 991014, optical observations
  31. Super-LOTIS optical observation of GRB991014
  32. BeppoSAX ALERT: GRB991014
  33. GRB 990915 optical observations
  34. GRB 990907 optical observations
  35. Optical Observations of GRB990907
  36. GRB990907: BeppoSAX follow up and X-ray afterglow
  37. GRB990907 and 990908
  38. GRB990907: refined WFC position
  39. GRB 990712 Late Optical Decay and Host Galaxy
  40. GRB 990712, Optical Observation
  41. GRB990806 BeppoSAX follow up
  42. GRB990806: BATSE Observations
  43. GRB 990806 Optical observations
  44. Optical Observations of GRB990806
  45. GRB 990806, Optical Observations
  46. GRB 990806, optical observations
  47. GRB 990806, Optical Observations
  48. GRB990806 UBVRIJHK observations
  49. BeppoSAX ALERT GRB990806: Summer GRB
  50. GRB 990712 Optical Observations
  51. GRB990705: No Evidence for Neutrino Signal
  52. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  53. VLT spectrum of GRB990712
  54. GRB 990712
  55. Late-time HST/STIS Observations of GRB 990510
  56. Refined BeppoSAX-WFC position of GRB990712
  57. GRB 990705, R-band observations
  58. Updated IPN localization of GRB990705
  59. Infrared and Optical Observations of GRB990705
  60. GRB 990705, radio observations
  61. GRB990704 radio and optical observations
  62. GRB 990704 X-ray Observations
  63. GRB 990704 Optical Observations
  64. GRB 990704, optical observations
  65. GRB990705: Intriguing Positional Coincidences
  66. GRB990704
  67. GRB990704, optical observations
  68. Identification of a possible optical counterpart for GRB990704
  69. GRB990704
  70. Refined BeppoSAX-WFC position of GRB990704
  71. GRB990704: BeppoSAX detection
  72. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  73. Optical Observations of GRB990627
  74. GRB 990627, radio observations
  75. BeppoSAX: GRB990625
  76. Late-time HST/STIS Observation of GRB 990123
  77. GRB 990506 - clarification to GCN 352
  78. GRB 990506 - Optical Observations
  79. Optical Observations of GRB 990506
  80. GRB990527 Optical Observations
  81. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  82. IPN error box for GRB990527
  83. Late Afterglows of GRBs 990510, 990123
  84. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  85. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  86. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  87. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  88. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  89. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  90. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  91. radio observations of X-ray/GRB transient field
  92. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  93. Optical report on X-ray/GRB transient
  94. radio detection of X-ray/GRB transient
  95. BeppoSAX: A new fast X-ray transient
  96. GRB 990510: optical observations
  97. GRB990510: photometric and spectroscopic observations with the VLT
  98. GRB 990510: optical linear polarization
  99. GRB 990510: optical observations
  100. GRB990510, VI observations

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