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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').
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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"

25045 results found.

  1. GRB 991216 Optical Observation
  2. GRB 991216: Extremely bright BATSE burst
  3. R-band Observations of GRB991208 at TNG
  4. GRB991208, optical observations
  5. GRB 991208, Optical Observation
  6. GRB991208, optical observations
  7. GRB 991208 optical observations
  8. Optical Observations of GRB991105
  9. GRB991106: BeppoSAX/BATSE results
  10. GRB991106, near-infrared observations
  11. BeppoSAX NFI Observation of GRB991106
  12. GRB 991106, radio observations
  13. GRB991106: the first BeppoSAX short GRB detection?
  14. GRB 991105: BATSE Observations
  15. GRB 991106 Optical Observations
  16. GRB991106, optical observation at SAO-RAS
  17. GRB 991106, LOTIS Optical Observations
  18. GRB991105: SAX-GRBM/-WFC detection
  19. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  20. GRB 991014, Optical Observations
  21. GRB 991014 - BeppoSAX NFI observations
  22. GRB 991014, radio observations
  23. GRB 991014, Optical Observations
  24. GRB 991014, optical observations
  25. GRB 990915 optical observations
  26. Optical Observations of GRB990907
  27. GRB990907: BeppoSAX follow up and X-ray afterglow
  28. GRB990907 and 990908
  29. GRB 990712 Late Optical Decay and Host Galaxy
  30. GRB990806 BeppoSAX follow up
  31. GRB990806: BATSE Observations
  32. GRB 990806 Optical observations
  33. GRB 990806, Optical Observations
  34. GRB 990806, optical observations
  35. GRB 990806, Optical Observations
  36. GRB990806 UBVRIJHK observations
  37. GRB 990712 Optical Observations
  38. GRB 990712
  39. Late-time HST/STIS Observations of GRB 990510
  40. BeppoSAX NFI Observation of GRB990705
  41. BeppoSAX NFI Observation of GRB990705
  42. GRB 990705, R-band observations
  43. Infrared and Optical Observations of GRB990705
  44. GRB990704: SAX-NFI results summary
  45. GRB990704 radio and optical observations
  46. GRB990704
  47. GRB990704, optical observations
  48. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  49. Optical Observations of GRB990627
  50. BeppoSAX: GRB990625
  51. Late-time HST/STIS Observation of GRB 990123
  52. Optical Observations of GRB 990506
  53. GRB990527 Optical Observations
  54. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  55. Late Afterglows of GRBs 990510, 990123
  56. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  57. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  58. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. radio observations of X-ray/GRB transient field
  63. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  64. Optical report on X-ray/GRB transient
  65. radio detection of X-ray/GRB transient
  66. BeppoSAX: A new fast X-ray transient
  67. GRB 990510: optical observations
  68. GRB 990510: optical linear polarization
  69. GRB 990510: optical observations
  70. GRB990510: X-ray afterglow
  71. GRB 990510: Broad Band Break
  72. GRB 990510: BATSE Observations
  73. GRB 990510: BeppoSAX/GRBM observations
  74. GRB990510 optical observations
  75. GRB 990510 optical observations
  76. GRB 990506 Radio Observations
  77. GRB 990123, optical monitoring
  78. GRB 990506: BATSE Observations
  79. GRB 990506, optical observations
  80. GRB 990506, Optical Observations
  81. GRB 990506 optical observations
  82. GRB 990506, optical observations
  83. GRB 990506, armchair astronomy
  84. GRB 990506, optical observations from +1 to +3 hours
  85. GRB 990506, optical observations
  86. GRB990506 observation plan
  87. IPN localization for GRB990506
  88. GRB990323 PRECISE IPN POSITION
  89. GRB 990316 Optical Observations
  90. GRB 990316 optical observations
  91. GRB990316: simultaneous optical observation
  92. GRB990316 - Optical null results
  93. GRB990308 not a new SGR
  94. GRB 990308a and GRB 990308b
  95. GRB990308, Possible new SGR~0209+70
  96. GRB 990123, Field Photometry
  97. GRB 990217 Optical Observations
  98. BATSE Flight Anomaly
  99. GRB990217: BeppoSAX/GRBM data
  100. GRB990123 observations

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