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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"

24603 results found.

  1. GRB000301C: RXTE/ASM and IPN localizations
  2. GRB000226 [IPN Position]
  3. HST Observations of GRB 990712
  4. GRB 000214 near-IR 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. Optical observations of GRB000210
  10. GRB000210 X-ray afterglow
  11. GRB000214: X-ray afterglow candidate
  12. GRB000214 refined BeppoSAX-WFC position
  13. GRB 000210: BATSE Observations
  14. Optical observations of the Chandra X-ray source for GRB000210
  15. GRB000210, Radio Observations
  16. IPN triangulation of GRB000210
  17. GRB000210: possible afterglow detection with BeppoSAX NFI
  18. GRB000201, Radio Observations
  19. GRB000210: BeppoSAX GRBM and WFC Detection
  20. SAX_WFC_GRB_NOTICE
  21. SAX_WFC_GRB_NOTICE
  22. GRB000201 Optical Observations
  23. GRB 000201: TAROT optical observations
  24. GRB 991208, radio observations
  25. BATSE+IPN location of GRB000131
  26. IPN localization of GRB000131
  27. GRB 000126, optical observations
  28. BATSE Observations of GRB000115
  29. Second RXTE Observation of GRB 000115
  30. GRB991216, UBVRIJHK field photometry
  31. GCN resumes full operations
  32. GRB 991216 VLBA Observations
  33. GRB 991216: J band spectrophotometry
  34. GRB 991216: Detection of the Host and/or Absorber Galaxy
  35. IPN localization of GRB991226
  36. GRB 991216 RXTE ASM Observations
  37. GRB 991216: Updated BATSE parameters
  38. GRB 991217 (SAX J2303.2+0015) Optical observations
  39. Chandra observation of the X-ray afterglow of GRB991216
  40. GRB 991216, optical observations
  41. GRB 991216 Optical spectroscopy/imaging
  42. SAX J2303.2+0015 Optical observations
  43. IR observations of GRB991216
  44. GRB 991217 (SAX J2303.2+0015) Optical observations
  45. GRB991216 Optical and infrared observations of Beethoven Burst
  46. GRB 991216 Radio Observations
  47. GRB 991208 Keck Spectroscopy
  48. GRB 991208 Infrared Detection
  49. GRB991216
  50. GRB 991216--Summary of RXTE Observations
  51. GRB 991216 Optical Observations
  52. GRB 991216, optical observations
  53. GRB 991208 SAO-RAS Spectroscopy
  54. SAX J2303.2+0015: an x-ray/GRB?
  55. GRB 991216, Optical Transient
  56. GRB991216 ('Beethoven Burst') B, R, and K Observations
  57. GRB991216, infrared observations
  58. GRB 991208 optical observations
  59. GRB 991216 Optical Observation
  60. GRB 991216: Extremely bright BATSE burst
  61. R-band Observations of GRB991208 at TNG
  62. GRB991208, optical observations
  63. GRB 991208, Optical Observation
  64. GRB991208, optical observations
  65. GRB 991208 optical observations
  66. Optical Observations of GRB991105
  67. GRB991106: BeppoSAX/BATSE results
  68. GRB991106, near-infrared observations
  69. BeppoSAX NFI Observation of GRB991106
  70. GRB 991106, radio observations
  71. GRB991106: the first BeppoSAX short GRB detection?
  72. GRB 991105: BATSE Observations
  73. GRB 991106 Optical Observations
  74. GRB991106, optical observation at SAO-RAS
  75. GRB 991106, LOTIS Optical Observations
  76. GRB991105: SAX-GRBM/-WFC detection
  77. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  78. GRB 991014, Optical Observations
  79. GRB 991014 - BeppoSAX NFI observations
  80. GRB 991014, radio observations
  81. GRB 991014, Optical Observations
  82. GRB 991014, optical observations
  83. GRB 990915 optical observations
  84. Optical Observations of GRB990907
  85. GRB990907: BeppoSAX follow up and X-ray afterglow
  86. GRB990907 and 990908
  87. GRB 990712 Late Optical Decay and Host Galaxy
  88. GRB990806 BeppoSAX follow up
  89. GRB990806: BATSE Observations
  90. GRB 990806 Optical observations
  91. GRB 990806, Optical Observations
  92. GRB 990806, optical observations
  93. GRB 990806, Optical Observations
  94. GRB990806 UBVRIJHK observations
  95. GRB 990712 Optical Observations
  96. GRB 990712
  97. Late-time HST/STIS Observations of GRB 990510
  98. BeppoSAX NFI Observation of GRB990705
  99. BeppoSAX NFI Observation of GRB990705
  100. GRB 990705, R-band observations

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