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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"

32130 results found.

  1. BATSE location of GRB000126
  2. IPN localization of GRB000126
  3. GRB 000115 Optical observations
  4. BATSE Observations of GRB000115
  5. Second RXTE Observation of GRB 000115
  6. GRB991216, UBVRIJHK field photometry
  7. Single IPN error box for GRB991229
  8. GRB 991216 VLBA Observations
  9. BEPPOSAX GRBM Localization of GRB991226
  10. IPN error boxes for GRB991229
  11. GRB 991216: J band spectrophotometry
  12. GRB 991216: Detection of the Host and/or Absorber Galaxy
  13. IPN localization of GRB991226
  14. Single IPN error box for GRB991221
  15. IPN error boxes for GRB991221
  16. GRB 991216 RXTE ASM Observations
  17. IPN error box for GRB991216
  18. GRB 991216: Updated BATSE parameters
  19. Lowell/Perkins observation of GRB 991216
  20. GRB 991217 (SAX J2303.2+0015) Optical observations
  21. Chandra observation of the X-ray afterglow of GRB991216
  22. GRB 991216, optical observations
  23. GRB 991216 Optical Observations
  24. GRB 991216 Optical spectroscopy/imaging
  25. K observations of GRB991216
  26. GRB 991217 (SAX J2303.2+0015) Optical observations
  27. GRB991216 Spectroscopy
  28. Lowell/Perkins observation of GRB 991216
  29. GRB991216, optical observations
  30. Refined IPN localization of GRB991216
  31. GRB 991216 Radio Observations
  32. GRB 991217
  33. GRB 991208 Keck Spectroscopy
  34. GRB 991208 Infrared Detection
  35. GRB 991216--Summary of RXTE Observations
  36. GRB 991216 Optical Observations
  37. GRB 991216, optical observations
  38. GRB 991208 SAO-RAS Spectroscopy
  39. SAX J2303.2+0015: an x-ray/GRB?
  40. GRB 991216, Optical Transient
  41. GRB 991216, Optical Afterglow
  42. GRB 991216: Comparison with DPOSS images
  43. GRB 991208 optical observations
  44. Lowell/Perkins observation of GRB 991216
  45. GRB 991216 Optical Observation
  46. GRB 991208 Keck Spectroscopy
  47. GRB 991216: Extremely bright BATSE burst
  48. GRB991208, optical observations
  49. GRB 991208 Keck Spectroscopy
  50. GRB991208 - millimeter detection
  51. GRB 991208, Optical Observation
  52. GRB 991208 - OVRO detection
  53. GRB 991208 Optical Decay
  54. GRB 991208 optical observations
  55. GRB 991208 optical observations
  56. GRB 991208: Radio Observations
  57. IPN localization of GRB991208
  58. Optical Observations of GRB991105
  59. GRB991106: BeppoSAX/BATSE results
  60. GRB 991106, optical observations
  61. GRB991106, near-infrared observations
  62. BeppoSAX NFI Observation of GRB991106
  63. GRB 991106, radio observations
  64. GRB991106: the first BeppoSAX short GRB detection?
  65. GRB 991105: BATSE Observations
  66. IPN localization of GRB991105
  67. GRB 991106 Optical Observations
  68. GRB 991105, optical observations
  69. GRB991106, optical observation at SAO-RAS
  70. GRB 991106, LOTIS Optical Observations
  71. GRB 991106, optical observations
  72. BeppoSAX GRB Alert: GRB991106
  73. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  74. GRB ALERT: GRB991105
  75. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  76. GRB 991014, Optical Observations
  77. GRB 991014 - BeppoSAX NFI observations
  78. GRB 991014, Optical Observations
  79. GRB 991014, radio observations
  80. GRB991014 BATSE Observations
  81. GRB 991014, Optical Observations
  82. GRB 991014, optical observations
  83. Super-LOTIS optical observation of GRB991014
  84. IPN/NFI error box for GRB991014
  85. IPN localization of GRB991014 - CORRECTION
  86. IPN localization of GRB991014
  87. BeppoSAX ALERT: GRB991014
  88. GRB 990915 optical observations
  89. GRB 990907 optical observations
  90. BATSE GRB trigger criteria
  91. Optical Observations of GRB990907
  92. IPN error box for GRB990915 (=BATSE 7766)
  93. IPN localization of BATSE #7766 (GRB990915)
  94. IPN localization of GRB990907
  95. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  96. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  97. GRB 990712 Late Optical Decay and Host Galaxy
  98. GRB 990712, Optical Observation
  99. GRB990806: BATSE Observations
  100. GRB 990806 Optical observations

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