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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"

35957 results found.

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

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