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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"

34090 results found.

  1. GRB 991216, Optical Afterglow
  2. GRB 991216: Comparison with DPOSS images
  3. GRB 991208 optical observations
  4. Lowell/Perkins observation of GRB 991216
  5. GRB 991216 Optical Observation
  6. GRB 991208 Keck Spectroscopy
  7. GRB 991216: Extremely bright BATSE burst
  8. GRB991208, optical observations
  9. GRB 991208 Keck Spectroscopy
  10. GRB991208 - millimeter detection
  11. GRB 991208, Optical Observation
  12. GRB 991208 - OVRO detection
  13. GRB 991208 Optical Decay
  14. GRB 991208 optical observations
  15. GRB 991208 optical observations
  16. GRB 991208: Radio Observations
  17. IPN localization of GRB991208
  18. Optical Observations of GRB991105
  19. GRB991106: BeppoSAX/BATSE results
  20. GRB 991106, optical observations
  21. GRB991106, near-infrared observations
  22. BeppoSAX NFI Observation of GRB991106
  23. GRB 991106, radio observations
  24. GRB991106: the first BeppoSAX short GRB detection?
  25. GRB 991105: BATSE Observations
  26. IPN localization of GRB991105
  27. GRB 991106 Optical Observations
  28. GRB 991105, optical observations
  29. GRB991106, optical observation at SAO-RAS
  30. GRB 991106, LOTIS Optical Observations
  31. GRB 991106, optical observations
  32. BeppoSAX GRB Alert: GRB991106
  33. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  34. GRB ALERT: GRB991105
  35. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  36. GRB 991014, Optical Observations
  37. GRB 991014 - BeppoSAX NFI observations
  38. GRB 991014, Optical Observations
  39. GRB 991014, radio observations
  40. GRB991014 BATSE Observations
  41. GRB 991014, Optical Observations
  42. GRB 991014, optical observations
  43. Super-LOTIS optical observation of GRB991014
  44. IPN/NFI error box for GRB991014
  45. IPN localization of GRB991014 - CORRECTION
  46. IPN localization of GRB991014
  47. BeppoSAX ALERT: GRB991014
  48. GRB 990915 optical observations
  49. GRB 990907 optical observations
  50. BATSE GRB trigger criteria
  51. Optical Observations of GRB990907
  52. IPN error box for GRB990915 (=BATSE 7766)
  53. IPN localization of BATSE #7766 (GRB990915)
  54. IPN localization of GRB990907
  55. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  56. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  57. GRB 990712 Late Optical Decay and Host Galaxy
  58. GRB 990712, Optical Observation
  59. GRB990806: BATSE Observations
  60. GRB 990806 Optical observations
  61. Optical Observations of GRB990806
  62. GRB 990806, Optical Observations
  63. GRB 990806, optical observations
  64. GRB 990806, Optical Observations
  65. GRB990806 UBVRIJHK observations
  66. BeppoSAX ALERT GRB990806: Summer GRB
  67. GRB 990712 Optical Observations
  68. GRB990705: No Evidence for Neutrino Signal
  69. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  70. VLT spectrum of GRB990712
  71. GRB 990712
  72. Late-time HST/STIS Observations of GRB 990510
  73. Refined BeppoSAX-WFC position of GRB990712
  74. GRB 990705, R-band observations
  75. Updated IPN localization of GRB990705
  76. IPN localization of GRB990704
  77. IPN localization of GRB990705
  78. Infrared and Optical Observations of GRB990705
  79. GRB 990705, radio observations
  80. GRB990704 radio and optical observations
  81. GRB 990704 X-ray Observations
  82. GRB 990704 Optical Observations
  83. GRB 990704, optical observations
  84. GRB990704
  85. GRB990705: Intriguing Positional Coincidences
  86. GRB990704
  87. GRB990704, optical observations
  88. Identification of a possible optical counterpart for GRB990704
  89. GRB990704
  90. Refined BeppoSAX-WFC position of GRB990704
  91. GRB990704: BeppoSAX detection
  92. Optical Observations of GRB990627
  93. GRB 990627, radio observations
  94. GRB990627: BeppoSAX-WFC final location
  95. BeppoSAX: GRB990625
  96. Late-time HST/STIS Observation of GRB 990123
  97. GRB 990506 - clarification to GCN 352
  98. GRB 990506 - Optical Observations
  99. Optical Observations of GRB 990506
  100. GRB 990506 Radio Transient

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