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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"

24846 results found.

  1. GRB 991208 optical observations
  2. GRB 991216 Optical Observation
  3. GRB 991216: Extremely bright BATSE burst
  4. R-band Observations of GRB991208 at TNG
  5. GRB991208, optical observations
  6. GRB 991208, Optical Observation
  7. GRB991208, optical observations
  8. GRB 991208 optical observations
  9. Optical Observations of GRB991105
  10. GRB991106: BeppoSAX/BATSE results
  11. GRB991106, near-infrared observations
  12. BeppoSAX NFI Observation of GRB991106
  13. GRB 991106, radio observations
  14. GRB991106: the first BeppoSAX short GRB detection?
  15. GRB 991105: BATSE Observations
  16. GRB 991106 Optical Observations
  17. GRB991106, optical observation at SAO-RAS
  18. GRB 991106, LOTIS Optical Observations
  19. GRB991105: SAX-GRBM/-WFC detection
  20. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  21. GRB 991014, Optical Observations
  22. GRB 991014 - BeppoSAX NFI observations
  23. GRB 991014, radio observations
  24. GRB 991014, Optical Observations
  25. GRB 991014, optical observations
  26. GRB 990915 optical observations
  27. Optical Observations of GRB990907
  28. GRB990907: BeppoSAX follow up and X-ray afterglow
  29. GRB990907 and 990908
  30. GRB 990712 Late Optical Decay and Host Galaxy
  31. GRB990806 BeppoSAX follow up
  32. GRB990806: BATSE Observations
  33. GRB 990806 Optical observations
  34. GRB 990806, Optical Observations
  35. GRB 990806, optical observations
  36. GRB 990806, Optical Observations
  37. GRB990806 UBVRIJHK observations
  38. GRB 990712 Optical Observations
  39. GRB 990712
  40. Late-time HST/STIS Observations of GRB 990510
  41. BeppoSAX NFI Observation of GRB990705
  42. BeppoSAX NFI Observation of GRB990705
  43. GRB 990705, R-band observations
  44. Infrared and Optical Observations of GRB990705
  45. GRB990704: SAX-NFI results summary
  46. GRB990704 radio and optical observations
  47. GRB990704
  48. GRB990704, optical observations
  49. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  50. Optical Observations of GRB990627
  51. BeppoSAX: GRB990625
  52. Late-time HST/STIS Observation of GRB 990123
  53. Optical Observations of GRB 990506
  54. GRB990527 Optical Observations
  55. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  56. Late Afterglows of GRBs 990510, 990123
  57. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  58. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  63. radio observations of X-ray/GRB transient field
  64. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  65. Optical report on X-ray/GRB transient
  66. radio detection of X-ray/GRB transient
  67. BeppoSAX: A new fast X-ray transient
  68. GRB 990510: optical observations
  69. GRB 990510: optical linear polarization
  70. GRB 990510: optical observations
  71. GRB990510: X-ray afterglow
  72. GRB 990510: Broad Band Break
  73. GRB 990510: BATSE Observations
  74. GRB 990510: BeppoSAX/GRBM observations
  75. GRB990510 optical observations
  76. GRB 990510 optical observations
  77. GRB 990506 Radio Observations
  78. GRB 990123, optical monitoring
  79. GRB 990506: BATSE Observations
  80. GRB 990506, optical observations
  81. GRB 990506, Optical Observations
  82. GRB 990506 optical observations
  83. GRB 990506, optical observations
  84. GRB 990506, armchair astronomy
  85. GRB 990506, optical observations from +1 to +3 hours
  86. GRB 990506, optical observations
  87. GRB990506 observation plan
  88. IPN localization for GRB990506
  89. GRB990323 PRECISE IPN POSITION
  90. GRB 990316 Optical Observations
  91. GRB 990316 optical observations
  92. GRB990316: simultaneous optical observation
  93. GRB990316 - Optical null results
  94. GRB990308 not a new SGR
  95. GRB 990308a and GRB 990308b
  96. GRB990308, Possible new SGR~0209+70
  97. GRB 990123, Field Photometry
  98. GRB 990217 Optical Observations
  99. BATSE Flight Anomaly
  100. GRB990217: BeppoSAX/GRBM data

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