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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"

35422 results found.

  1. IPN error boxes for GRB991229
  2. GRB 991216: J band spectrophotometry
  3. GRB 991216: Detection of the Host and/or Absorber Galaxy
  4. IPN localization of GRB991226
  5. Single IPN error box for GRB991221
  6. IPN error boxes for GRB991221
  7. GRB 991216 RXTE ASM Observations
  8. IPN error box for GRB991216
  9. GRB 991216: Updated BATSE parameters
  10. Lowell/Perkins observation of GRB 991216
  11. GRB 991217 (SAX J2303.2+0015) Optical observations
  12. Chandra observation of the X-ray afterglow of GRB991216
  13. GRB 991216, optical observations
  14. GRB 991216 Optical Observations
  15. GRB 991216 Optical spectroscopy/imaging
  16. K observations of GRB991216
  17. GRB 991217 (SAX J2303.2+0015) Optical observations
  18. GRB991216 Spectroscopy
  19. Lowell/Perkins observation of GRB 991216
  20. GRB991216, optical observations
  21. Refined IPN localization of GRB991216
  22. GRB 991216 Radio Observations
  23. GRB 991217
  24. GRB 991208 Keck Spectroscopy
  25. GRB 991208 Infrared Detection
  26. GRB 991216--Summary of RXTE Observations
  27. GRB 991216 Optical Observations
  28. GRB 991216, optical observations
  29. GRB 991208 SAO-RAS Spectroscopy
  30. SAX J2303.2+0015: an x-ray/GRB?
  31. GRB 991216, Optical Transient
  32. GRB 991216, Optical Afterglow
  33. GRB 991216: Comparison with DPOSS images
  34. GRB 991208 optical observations
  35. Lowell/Perkins observation of GRB 991216
  36. GRB 991216 Optical Observation
  37. GRB 991208 Keck Spectroscopy
  38. GRB 991216: Extremely bright BATSE burst
  39. GRB991208, optical observations
  40. GRB 991208 Keck Spectroscopy
  41. GRB991208 - millimeter detection
  42. GRB 991208, Optical Observation
  43. GRB 991208 - OVRO detection
  44. GRB 991208 Optical Decay
  45. GRB 991208 optical observations
  46. GRB 991208 optical observations
  47. GRB 991208: Radio Observations
  48. IPN localization of GRB991208
  49. Optical Observations of GRB991105
  50. GRB991106: BeppoSAX/BATSE results
  51. GRB 991106, optical observations
  52. GRB991106, near-infrared observations
  53. BeppoSAX NFI Observation of GRB991106
  54. GRB 991106, radio observations
  55. GRB991106: the first BeppoSAX short GRB detection?
  56. GRB 991105: BATSE Observations
  57. IPN localization of GRB991105
  58. GRB 991106 Optical Observations
  59. GRB 991105, optical observations
  60. GRB991106, optical observation at SAO-RAS
  61. GRB 991106, LOTIS Optical Observations
  62. GRB 991106, optical observations
  63. BeppoSAX GRB Alert: GRB991106
  64. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  65. GRB ALERT: GRB991105
  66. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  67. GRB 991014, Optical Observations
  68. GRB 991014 - BeppoSAX NFI observations
  69. GRB 991014, Optical Observations
  70. GRB 991014, radio observations
  71. GRB991014 BATSE Observations
  72. GRB 991014, Optical Observations
  73. GRB 991014, optical observations
  74. Super-LOTIS optical observation of GRB991014
  75. IPN/NFI error box for GRB991014
  76. IPN localization of GRB991014 - CORRECTION
  77. IPN localization of GRB991014
  78. BeppoSAX ALERT: GRB991014
  79. GRB 990915 optical observations
  80. GRB 990907 optical observations
  81. BATSE GRB trigger criteria
  82. Optical Observations of GRB990907
  83. IPN error box for GRB990915 (=BATSE 7766)
  84. IPN localization of BATSE #7766 (GRB990915)
  85. IPN localization of GRB990907
  86. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  87. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  88. GRB 990712 Late Optical Decay and Host Galaxy
  89. GRB 990712, Optical Observation
  90. GRB990806: BATSE Observations
  91. GRB 990806 Optical observations
  92. Optical Observations of GRB990806
  93. GRB 990806, Optical Observations
  94. GRB 990806, optical observations
  95. GRB 990806, Optical Observations
  96. GRB990806 UBVRIJHK observations
  97. BeppoSAX ALERT GRB990806: Summer GRB
  98. GRB 990712 Optical Observations
  99. GRB990705: No Evidence for Neutrino Signal
  100. GRB 990712 Optical Decay: Indication of Bright Host Galaxy

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