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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"

24847 results found.

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

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