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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"

27148 results found.

  1. GRB991216 ('Beethoven Burst') B, R, and K Observations
  2. GRB991216, infrared observations
  3. GRB 991208 optical observations
  4. GRB 991216 Optical Observation
  5. GRB 991216: Extremely bright BATSE burst
  6. R-band Observations of GRB991208 at TNG
  7. GRB991208, optical observations
  8. GRB 991208, Optical Observation
  9. GRB991208, optical observations
  10. GRB 991208 optical observations
  11. Optical Observations of GRB991105
  12. GRB991106: BeppoSAX/BATSE results
  13. GRB991106, near-infrared observations
  14. BeppoSAX NFI Observation of GRB991106
  15. GRB 991106, radio observations
  16. GRB991106: the first BeppoSAX short GRB detection?
  17. GRB 991105: BATSE Observations
  18. GRB 991106 Optical Observations
  19. GRB991106, optical observation at SAO-RAS
  20. GRB 991106, LOTIS Optical Observations
  21. GRB991105: SAX-GRBM/-WFC detection
  22. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  23. GRB 991014, Optical Observations
  24. GRB 991014 - BeppoSAX NFI observations
  25. GRB 991014, radio observations
  26. GRB 991014, Optical Observations
  27. GRB 991014, optical observations
  28. GRB 990915 optical observations
  29. Optical Observations of GRB990907
  30. GRB990907: BeppoSAX follow up and X-ray afterglow
  31. GRB990907 and 990908
  32. GRB 990712 Late Optical Decay and Host Galaxy
  33. GRB990806 BeppoSAX follow up
  34. GRB990806: BATSE Observations
  35. GRB 990806 Optical observations
  36. GRB 990806, Optical Observations
  37. GRB 990806, optical observations
  38. GRB 990806, Optical Observations
  39. GRB990806 UBVRIJHK observations
  40. GRB 990712 Optical Observations
  41. GRB 990712
  42. Late-time HST/STIS Observations of GRB 990510
  43. BeppoSAX NFI Observation of GRB990705
  44. BeppoSAX NFI Observation of GRB990705
  45. GRB 990705, R-band observations
  46. Infrared and Optical Observations of GRB990705
  47. GRB990704: SAX-NFI results summary
  48. GRB990704 radio and optical observations
  49. GRB990704
  50. GRB990704, optical observations
  51. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  52. Optical Observations of GRB990627
  53. BeppoSAX: GRB990625
  54. Late-time HST/STIS Observation of GRB 990123
  55. Optical Observations of GRB 990506
  56. GRB990527 Optical Observations
  57. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  58. Late Afterglows of GRBs 990510, 990123
  59. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  60. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  62. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  63. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  64. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  65. radio observations of X-ray/GRB transient field
  66. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  67. Optical report on X-ray/GRB transient
  68. radio detection of X-ray/GRB transient
  69. BeppoSAX: A new fast X-ray transient
  70. GRB 990510: optical observations
  71. GRB 990510: optical linear polarization
  72. GRB 990510: optical observations
  73. GRB990510: X-ray afterglow
  74. GRB 990510: Broad Band Break
  75. GRB 990510: BATSE Observations
  76. GRB 990510: BeppoSAX/GRBM observations
  77. GRB990510 optical observations
  78. GRB 990510 optical observations
  79. GRB 990506 Radio Observations
  80. GRB 990123, optical monitoring
  81. GRB 990506: BATSE Observations
  82. GRB 990506, optical observations
  83. GRB 990506, Optical Observations
  84. GRB 990506 optical observations
  85. GRB 990506, optical observations
  86. GRB 990506, armchair astronomy
  87. GRB 990506, optical observations from +1 to +3 hours
  88. GRB 990506, optical observations
  89. GRB990506 observation plan
  90. IPN localization for GRB990506
  91. GRB990323 PRECISE IPN POSITION
  92. GRB 990316 Optical Observations
  93. GRB 990316 optical observations
  94. GRB990316: simultaneous optical observation
  95. GRB990316 - Optical null results
  96. GRB990308 not a new SGR
  97. GRB 990308a and GRB 990308b
  98. GRB990308, Possible new SGR~0209+70
  99. GRB 990123, Field Photometry
  100. GRB 990217 Optical Observations

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