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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"

36155 results found.

  1. GRB 000214 near-IR observations
  2. GRB 000115 Optical observations
  3. GRB 000214, Radio Observations
  4. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  5. GRB 000115, BVRI field photometry
  6. IPN annulus for GRB000214
  7. BATSE GRB trigger criterion changed
  8. GRB000210 X-ray afterglow
  9. GRB000214: X-ray afterglow candidate
  10. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  11. GRB 000210: BATSE Observations
  12. Optical observations of the Chandra X-ray source for GRB000210
  13. Chandra Observations of GRB000210 X-ray Afterglow
  14. IPN triangulation of GRB000210
  15. GRB 000201: TAROT optical observations
  16. GRB 000131 Optical Observations
  17. GRB000126 Optical Observations
  18. BATSE GRB trigger criteria changed
  19. GRB 991208, radio observations
  20. BATSE+IPN location of GRB000131
  21. IPN localization of GRB000131
  22. GRB 000126, optical observations
  23. GRB000126, optical observations
  24. BATSE location of GRB000126
  25. IPN localization of GRB000126
  26. GRB 000115 Optical observations
  27. BATSE Observations of GRB000115
  28. Second RXTE Observation of GRB 000115
  29. GRB991216, UBVRIJHK field photometry
  30. Single IPN error box for GRB991229
  31. GCN resumes full operations
  32. GRB 991216 VLBA Observations
  33. BEPPOSAX GRBM Localization of GRB991226
  34. IPN error boxes for GRB991229
  35. GRB 991216: J band spectrophotometry
  36. GRB 991216: Detection of the Host and/or Absorber Galaxy
  37. IPN localization of GRB991226
  38. Single IPN error box for GRB991221
  39. IPN error boxes for GRB991221
  40. GRB 991216 RXTE ASM Observations
  41. IPN error box for GRB991216
  42. GRB 991216: Updated BATSE parameters
  43. Lowell/Perkins observation of GRB 991216
  44. GRB 991217 (SAX J2303.2+0015) Optical observations
  45. Chandra observation of the X-ray afterglow of GRB991216
  46. GRB 991216, optical observations
  47. GRB 991216 Optical Observations
  48. GRB 991216 Optical spectroscopy/imaging
  49. K observations of GRB991216
  50. GRB 991217 (SAX J2303.2+0015) Optical observations
  51. GRB991216 Spectroscopy
  52. Lowell/Perkins observation of GRB 991216
  53. GRB991216, optical observations
  54. Refined IPN localization of GRB991216
  55. GRB 991216 Radio Observations
  56. GRB 991217
  57. GRB 991208 Keck Spectroscopy
  58. GRB 991208 Infrared Detection
  59. GRB 991216--Summary of RXTE Observations
  60. GRB 991216 Optical Observations
  61. GRB 991216, optical observations
  62. GRB 991208 SAO-RAS Spectroscopy
  63. SAX J2303.2+0015: an x-ray/GRB?
  64. GRB 991216, Optical Transient
  65. GRB 991216, Optical Afterglow
  66. GRB 991216: Comparison with DPOSS images
  67. GRB 991208 optical observations
  68. Lowell/Perkins observation of GRB 991216
  69. GRB 991216 Optical Observation
  70. GRB 991208 Keck Spectroscopy
  71. GRB 991216: Extremely bright BATSE burst
  72. GRB991208, optical observations
  73. GRB 991208 Keck Spectroscopy
  74. GRB991208 - millimeter detection
  75. GRB 991208, Optical Observation
  76. GRB 991208 - OVRO detection
  77. GRB 991208 Optical Decay
  78. GRB 991208 optical observations
  79. GRB 991208 optical observations
  80. GRB 991208: Radio Observations
  81. IPN localization of GRB991208
  82. Optical Observations of GRB991105
  83. GRB991106: BeppoSAX/BATSE results
  84. GRB 991106, optical observations
  85. GRB991106, near-infrared observations
  86. BeppoSAX NFI Observation of GRB991106
  87. GRB 991106, radio observations
  88. GRB991106: the first BeppoSAX short GRB detection?
  89. GRB 991105: BATSE Observations
  90. IPN localization of GRB991105
  91. GRB 991106 Optical Observations
  92. GRB 991105, optical observations
  93. GRB991106, optical observation at SAO-RAS
  94. GRB 991106, LOTIS Optical Observations
  95. GRB 991106, optical observations
  96. BeppoSAX GRB Alert: GRB991106
  97. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  98. GRB ALERT: GRB991105
  99. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  100. GRB 991014, Optical Observations

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