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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"

19863 results found.

  1. GRB000226 [IPN Position]
  2. HST Observations of GRB 990712
  3. GRB 000214 near-IR observations
  4. GRB 000214, Radio Observations
  5. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  6. GRB000210, Radio Observations
  7. GRB 000115, BVRI field photometry
  8. GRB000214: BeppoSAX GRBM and WFC Detection
  9. BATSE GRB trigger criterion changed
  10. Optical observations of GRB000210
  11. GRB000210 X-ray afterglow
  12. GRB000214: X-ray afterglow candidate
  13. GRB000214 refined BeppoSAX-WFC position
  14. Optical observations of the Chandra X-ray source for GRB000210
  15. GRB000210, Radio Observations
  16. GRB000201, Radio Observations
  17. GRB000210: BeppoSAX GRBM and WFC Detection
  18. GRB000201 Optical Observations
  19. GRB 000131 Optical Observations
  20. GRB000126 Optical Observations
  21. BATSE GRB trigger criteria changed
  22. BATSE+IPN location of GRB000131
  23. IPN localization of GRB000131
  24. GRB 000126, optical observations
  25. GRB991216, UBVRIJHK field photometry
  26. GCN resumes full operations
  27. IPN error boxes for GRB991229
  28. GRB 991216: J band spectrophotometry
  29. GRB 991216: Detection of the Host and/or Absorber Galaxy
  30. GRB 991216 RXTE ASM Observations
  31. GRB 991216: Updated BATSE parameters
  32. GRB 991217 (SAX J2303.2+0015) Optical observations
  33. Chandra observation of the X-ray afterglow of GRB991216
  34. SAX J2303.2+0015 Optical observations
  35. IR observations of GRB991216
  36. GRB 991217 (SAX J2303.2+0015) Optical observations
  37. GRB 991216 Radio Observations
  38. GRB 991208 Keck Spectroscopy
  39. GRB 991208 Infrared Detection
  40. GRB991216
  41. GRB 991216--Summary of RXTE Observations
  42. GRB 991216 Optical Observations
  43. GRB 991216, optical observations
  44. GRB 991208 SAO-RAS Spectroscopy
  45. SAX J2303.2+0015: an x-ray/GRB?
  46. GRB 991216, Optical Transient
  47. GRB991216 ('Beethoven Burst') B, R, and K Observations
  48. GRB991216, infrared observations
  49. GRB 991208 optical observations
  50. GRB 991216 Optical Observation
  51. GRB 991208 Keck Spectroscopy
  52. GRB 991216: Extremely bright BATSE burst
  53. GRB991208, optical observations
  54. GRB 991208, Optical Observation
  55. GRB991208, optical observations
  56. GRB 991208 Optical Decay
  57. IPN localization of GRB991208
  58. Optical Observations of GRB991105
  59. GRB991106: BeppoSAX/BATSE results
  60. BeppoSAX NFI Observation of GRB991106
  61. GRB 991106, radio observations
  62. GRB991106: the first BeppoSAX short GRB detection?
  63. GRB 991106 Optical Observations
  64. GRB991106, optical observation at SAO-RAS
  65. GRB 991106, LOTIS Optical Observations
  66. BeppoSAX GRB Alert: GRB991106
  67. GRB991105: SAX-GRBM/-WFC detection
  68. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  69. GRB 991014, Optical Observations
  70. GRB 991014 - BeppoSAX NFI observations
  71. GRB 991014, radio observations
  72. GRB 991014, Optical Observations
  73. GRB 991014, optical observations
  74. Optical Observations of GRB990907
  75. GRB990907: BeppoSAX follow up and X-ray afterglow
  76. GRB990907 and 990908
  77. GRB 990712 Late Optical Decay and Host Galaxy
  78. GRB 990712, Optical Observation
  79. GRB990806 BeppoSAX follow up
  80. GRB 990806 Optical observations
  81. GRB 990806, optical observations
  82. GRB 990806, Optical Observations
  83. GRB 990712 Optical Observations
  84. GRB 990712
  85. Late-time HST/STIS Observations of GRB 990510
  86. BeppoSAX NFI Observation of GRB990705
  87. BeppoSAX NFI Observation of GRB990705
  88. GRB 990705, R-band observations
  89. GRB990704: SAX-NFI results summary
  90. GRB990704 radio and optical observations
  91. GRB990704
  92. GRB990704, optical observations
  93. GRB990704
  94. Refined BeppoSAX-WFC position of GRB990704
  95. GRB990704: BeppoSAX detection
  96. Late-time HST/STIS Observation of GRB 990123
  97. Optical Observations of GRB 990506
  98. GRB990527 Optical Observations
  99. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  100. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation

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