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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"

28037 results found.

  1. GRB991106: BeppoSAX/BATSE results
  2. GRB991106, near-infrared observations
  3. BeppoSAX NFI Observation of GRB991106
  4. GRB 991106, radio observations
  5. GRB991106: the first BeppoSAX short GRB detection?
  6. GRB 991105: BATSE Observations
  7. GRB 991106 Optical Observations
  8. GRB991106, optical observation at SAO-RAS
  9. GRB 991106, LOTIS Optical Observations
  10. GRB991105: SAX-GRBM/-WFC detection
  11. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  12. GRB 991014, Optical Observations
  13. GRB 991014 - BeppoSAX NFI observations
  14. GRB 991014, radio observations
  15. GRB 991014, Optical Observations
  16. GRB 991014, optical observations
  17. GRB 990915 optical observations
  18. Optical Observations of GRB990907
  19. GRB990907: BeppoSAX follow up and X-ray afterglow
  20. GRB990907 and 990908
  21. GRB 990712 Late Optical Decay and Host Galaxy
  22. GRB990806 BeppoSAX follow up
  23. GRB990806: BATSE Observations
  24. GRB 990806 Optical observations
  25. GRB 990806, Optical Observations
  26. GRB 990806, optical observations
  27. GRB 990806, Optical Observations
  28. GRB990806 UBVRIJHK observations
  29. GRB 990712 Optical Observations
  30. GRB 990712
  31. Late-time HST/STIS Observations of GRB 990510
  32. BeppoSAX NFI Observation of GRB990705
  33. BeppoSAX NFI Observation of GRB990705
  34. GRB 990705, R-band observations
  35. Infrared and Optical Observations of GRB990705
  36. GRB990704: SAX-NFI results summary
  37. GRB990704 radio and optical observations
  38. GRB990704
  39. GRB990704, optical observations
  40. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  41. Optical Observations of GRB990627
  42. BeppoSAX: GRB990625
  43. Late-time HST/STIS Observation of GRB 990123
  44. Optical Observations of GRB 990506
  45. GRB990527 Optical Observations
  46. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  47. Late Afterglows of GRBs 990510, 990123
  48. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  49. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  50. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  51. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  52. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  53. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  54. radio observations of X-ray/GRB transient field
  55. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  56. Optical report on X-ray/GRB transient
  57. radio detection of X-ray/GRB transient
  58. BeppoSAX: A new fast X-ray transient
  59. GRB 990510: optical observations
  60. GRB 990510: optical linear polarization
  61. GRB 990510: optical observations
  62. GRB990510: X-ray afterglow
  63. GRB 990510: Broad Band Break
  64. GRB 990510: BATSE Observations
  65. GRB 990510: BeppoSAX/GRBM observations
  66. GRB990510 optical observations
  67. GRB 990510 optical observations
  68. GRB 990506 Radio Observations
  69. GRB 990123, optical monitoring
  70. GRB 990506: BATSE Observations
  71. GRB 990506, optical observations
  72. GRB 990506, Optical Observations
  73. GRB 990506 optical observations
  74. GRB 990506, optical observations
  75. GRB 990506, armchair astronomy
  76. GRB 990506, optical observations from +1 to +3 hours
  77. GRB 990506, optical observations
  78. GRB990506 observation plan
  79. IPN localization for GRB990506
  80. GRB990323 PRECISE IPN POSITION
  81. GRB 990316 Optical Observations
  82. GRB 990316 optical observations
  83. GRB990316: simultaneous optical observation
  84. GRB990316 - Optical null results
  85. GRB990308 not a new SGR
  86. GRB 990308a and GRB 990308b
  87. GRB990308, Possible new SGR~0209+70
  88. GRB 990123, Field Photometry
  89. GRB 990217 Optical Observations
  90. BATSE Flight Anomaly
  91. GRB990217: BeppoSAX/GRBM data
  92. GRB990123 observations
  93. GRB990217 Optical observation
  94. GRB990123, Optical Observation
  95. GRB 990123: Discovery of the Probable Host Galaxy
  96. GRB 990123: Reduced HST Images
  97. GRB19990123 observations
  98. GRB 990123: BVRI standards in the field
  99. GRB981220, field photometry
  100. GRB990123, Optical observation

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