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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"

16214 results found.

  1. GRB000301c optical observations
  2. GRB000301C
  3. GRB 000301C : Optical Candidate
  4. HST Observations of GRB 990712
  5. GRB 000214 near-IR observations
  6. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  7. GRB000210, Radio Observations
  8. GRB 000115, BVRI field photometry
  9. GRB000214: BeppoSAX GRBM and WFC Detection
  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 000126, optical observations
  20. GRB991216, UBVRIJHK field photometry
  21. GCN resumes full operations
  22. GRB 991216: Detection of the Host and/or Absorber Galaxy
  23. IPN error box for GRB991216
  24. GRB 991217 (SAX J2303.2+0015) Optical observations
  25. Chandra observation of the X-ray afterglow of GRB991216
  26. SAX J2303.2+0015 Optical observations
  27. IR observations of GRB991216
  28. GRB 991217 (SAX J2303.2+0015) Optical observations
  29. GRB 991216 Radio Observations
  30. GRB 991208 Infrared Detection
  31. GRB991216
  32. GRB 991216--Summary of RXTE Observations
  33. GRB 991216 Optical Observations
  34. GRB 991216, optical observations
  35. GRB 991208 SAO-RAS Spectroscopy
  36. SAX J2303.2+0015: an x-ray/GRB?
  37. GRB 991216, Optical Transient
  38. GRB991216 ('Beethoven Burst') B, R, and K Observations
  39. GRB991216, infrared observations
  40. GRB 991208 optical observations
  41. GRB 991216 Optical Observation
  42. GRB 991216: Extremely bright BATSE burst
  43. GRB991208, optical observations
  44. GRB 991208, Optical Observation
  45. GRB991208, optical observations
  46. Optical Observations of GRB991105
  47. GRB991106: BeppoSAX/BATSE results
  48. BeppoSAX NFI Observation of GRB991106
  49. GRB 991106, radio observations
  50. GRB991106: the first BeppoSAX short GRB detection?
  51. GRB 991106 Optical Observations
  52. GRB991106, optical observation at SAO-RAS
  53. GRB 991106, LOTIS Optical Observations
  54. GRB991105: SAX-GRBM/-WFC detection
  55. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  56. GRB 991014, Optical Observations
  57. GRB 991014 - BeppoSAX NFI observations
  58. GRB 991014, radio observations
  59. GRB 991014, Optical Observations
  60. GRB 991014, optical observations
  61. Super-LOTIS optical observation of GRB991014
  62. Optical Observations of GRB990907
  63. GRB990907 and 990908
  64. GRB990806 BeppoSAX follow up
  65. GRB 990806 Optical observations
  66. GRB 990806, optical observations
  67. GRB 990806, Optical Observations
  68. GRB 990712 Optical Observations
  69. GRB 990712
  70. Late-time HST/STIS Observations of GRB 990510
  71. BeppoSAX NFI Observation of GRB990705
  72. BeppoSAX NFI Observation of GRB990705
  73. GRB 990705, R-band observations
  74. GRB990704: SAX-NFI results summary
  75. GRB990704 radio and optical observations
  76. GRB990704
  77. GRB990704, optical observations
  78. Late-time HST/STIS Observation of GRB 990123
  79. Optical Observations of GRB 990506
  80. GRB990527 Optical Observations
  81. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  82. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  83. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  84. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  85. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  86. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  87. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  88. radio observations of X-ray/GRB transient field
  89. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  90. Optical report on X-ray/GRB transient
  91. GRB 990510: optical linear polarization
  92. GRB 990510: optical observations
  93. GRB 990506 R band observations
  94. GRB 990510: BATSE Observations
  95. GRB 990510 optical observations
  96. GRB 990506 Radio Observations
  97. GRB 990123, optical monitoring
  98. GRB 990506, optical observations
  99. GRB 990506, Optical Observations
  100. GRB 990506 optical observations

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