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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"

35152 results found.

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

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