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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"

28043 results found.

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

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