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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"

25751 results found.

  1. GRB 991208 SAO-RAS Spectroscopy
  2. SAX J2303.2+0015: an x-ray/GRB?
  3. GRB 991216, Optical Transient
  4. GRB991216 ('Beethoven Burst') B, R, and K Observations
  5. GRB991216, infrared observations
  6. GRB 991208 optical observations
  7. GRB 991216 Optical Observation
  8. GRB 991216: Extremely bright BATSE burst
  9. R-band Observations of GRB991208 at TNG
  10. GRB991208, optical observations
  11. GRB 991208, Optical Observation
  12. GRB991208, optical observations
  13. GRB 991208 optical observations
  14. Optical Observations of GRB991105
  15. GRB991106: BeppoSAX/BATSE results
  16. GRB991106, near-infrared observations
  17. BeppoSAX NFI Observation of GRB991106
  18. GRB 991106, radio observations
  19. GRB991106: the first BeppoSAX short GRB detection?
  20. GRB 991105: BATSE Observations
  21. GRB 991106 Optical Observations
  22. GRB991106, optical observation at SAO-RAS
  23. GRB 991106, LOTIS Optical Observations
  24. GRB991105: SAX-GRBM/-WFC detection
  25. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  26. GRB 991014, Optical Observations
  27. GRB 991014 - BeppoSAX NFI observations
  28. GRB 991014, radio observations
  29. GRB 991014, Optical Observations
  30. GRB 991014, optical observations
  31. GRB 990915 optical observations
  32. Optical Observations of GRB990907
  33. GRB990907: BeppoSAX follow up and X-ray afterglow
  34. GRB990907 and 990908
  35. GRB 990712 Late Optical Decay and Host Galaxy
  36. GRB990806 BeppoSAX follow up
  37. GRB990806: BATSE Observations
  38. GRB 990806 Optical observations
  39. GRB 990806, Optical Observations
  40. GRB 990806, optical observations
  41. GRB 990806, Optical Observations
  42. GRB990806 UBVRIJHK observations
  43. GRB 990712 Optical Observations
  44. GRB 990712
  45. Late-time HST/STIS Observations of GRB 990510
  46. BeppoSAX NFI Observation of GRB990705
  47. BeppoSAX NFI Observation of GRB990705
  48. GRB 990705, R-band observations
  49. Infrared and Optical Observations of GRB990705
  50. GRB990704: SAX-NFI results summary
  51. GRB990704 radio and optical observations
  52. GRB990704
  53. GRB990704, optical observations
  54. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  55. Optical Observations of GRB990627
  56. BeppoSAX: GRB990625
  57. Late-time HST/STIS Observation of GRB 990123
  58. Optical Observations of GRB 990506
  59. GRB990527 Optical Observations
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  61. Late Afterglows of GRBs 990510, 990123
  62. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  63. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  64. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  65. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  67. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  68. radio observations of X-ray/GRB transient field
  69. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  70. Optical report on X-ray/GRB transient
  71. radio detection of X-ray/GRB transient
  72. BeppoSAX: A new fast X-ray transient
  73. GRB 990510: optical observations
  74. GRB 990510: optical linear polarization
  75. GRB 990510: optical observations
  76. GRB990510: X-ray afterglow
  77. GRB 990510: Broad Band Break
  78. GRB 990510: BATSE Observations
  79. GRB 990510: BeppoSAX/GRBM observations
  80. GRB990510 optical observations
  81. GRB 990510 optical observations
  82. GRB 990506 Radio Observations
  83. GRB 990123, optical monitoring
  84. GRB 990506: BATSE Observations
  85. GRB 990506, optical observations
  86. GRB 990506, Optical Observations
  87. GRB 990506 optical observations
  88. GRB 990506, optical observations
  89. GRB 990506, armchair astronomy
  90. GRB 990506, optical observations from +1 to +3 hours
  91. GRB 990506, optical observations
  92. GRB990506 observation plan
  93. IPN localization for GRB990506
  94. GRB990323 PRECISE IPN POSITION
  95. GRB 990316 Optical Observations
  96. GRB 990316 optical observations
  97. GRB990316: simultaneous optical observation
  98. GRB990316 - Optical null results
  99. GRB990308 not a new SGR
  100. GRB 990308a and GRB 990308b

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