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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"

24934 results found.

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

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