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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"

24808 results found.

  1. GRB 000301C: OT confirmed
  2. GRB000301c optical observations
  3. GRB000301C, optical observations
  4. GRB000301C
  5. GRB 000301C : Optical Candidate
  6. GRB000301C: RXTE/ASM and IPN localizations
  7. GRB000226 [IPN Position]
  8. HST Observations of GRB 990712
  9. GRB 000214 near-IR observations
  10. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  11. GRB000210, Radio Observations
  12. GRB 000115, BVRI field photometry
  13. GRB000214: BeppoSAX GRBM and WFC Detection
  14. Optical observations of GRB000210
  15. GRB000210 X-ray afterglow
  16. GRB000214: X-ray afterglow candidate
  17. GRB000214 refined BeppoSAX-WFC position
  18. GRB 000210: BATSE Observations
  19. Optical observations of the Chandra X-ray source for GRB000210
  20. GRB000210, Radio Observations
  21. IPN triangulation of GRB000210
  22. GRB000210: possible afterglow detection with BeppoSAX NFI
  23. GRB000201, Radio Observations
  24. GRB000210: BeppoSAX GRBM and WFC Detection
  25. SAX_WFC_GRB_NOTICE
  26. SAX_WFC_GRB_NOTICE
  27. GRB000201 Optical Observations
  28. GRB 000201: TAROT optical observations
  29. GRB 991208, radio observations
  30. BATSE+IPN location of GRB000131
  31. IPN localization of GRB000131
  32. GRB 000126, optical observations
  33. BATSE Observations of GRB000115
  34. Second RXTE Observation of GRB 000115
  35. GRB991216, UBVRIJHK field photometry
  36. GCN resumes full operations
  37. GRB 991216 VLBA Observations
  38. GRB 991216: J band spectrophotometry
  39. GRB 991216: Detection of the Host and/or Absorber Galaxy
  40. IPN localization of GRB991226
  41. GRB 991216 RXTE ASM Observations
  42. GRB 991216: Updated BATSE parameters
  43. GRB 991217 (SAX J2303.2+0015) Optical observations
  44. Chandra observation of the X-ray afterglow of GRB991216
  45. GRB 991216, optical observations
  46. GRB 991216 Optical spectroscopy/imaging
  47. SAX J2303.2+0015 Optical observations
  48. IR observations of GRB991216
  49. GRB 991217 (SAX J2303.2+0015) Optical observations
  50. GRB991216 Optical and infrared observations of Beethoven Burst
  51. GRB 991216 Radio Observations
  52. GRB 991208 Keck Spectroscopy
  53. GRB 991208 Infrared Detection
  54. GRB991216
  55. GRB 991216--Summary of RXTE Observations
  56. GRB 991216 Optical Observations
  57. GRB 991216, optical observations
  58. GRB 991208 SAO-RAS Spectroscopy
  59. SAX J2303.2+0015: an x-ray/GRB?
  60. GRB 991216, Optical Transient
  61. GRB991216 ('Beethoven Burst') B, R, and K Observations
  62. GRB991216, infrared observations
  63. GRB 991208 optical observations
  64. GRB 991216 Optical Observation
  65. GRB 991216: Extremely bright BATSE burst
  66. R-band Observations of GRB991208 at TNG
  67. GRB991208, optical observations
  68. GRB 991208, Optical Observation
  69. GRB991208, optical observations
  70. GRB 991208 optical observations
  71. Optical Observations of GRB991105
  72. GRB991106: BeppoSAX/BATSE results
  73. GRB991106, near-infrared observations
  74. BeppoSAX NFI Observation of GRB991106
  75. GRB 991106, radio observations
  76. GRB991106: the first BeppoSAX short GRB detection?
  77. GRB 991105: BATSE Observations
  78. GRB 991106 Optical Observations
  79. GRB991106, optical observation at SAO-RAS
  80. GRB 991106, LOTIS Optical Observations
  81. GRB991105: SAX-GRBM/-WFC detection
  82. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  83. GRB 991014, Optical Observations
  84. GRB 991014 - BeppoSAX NFI observations
  85. GRB 991014, radio observations
  86. GRB 991014, Optical Observations
  87. GRB 991014, optical observations
  88. GRB 990915 optical observations
  89. Optical Observations of GRB990907
  90. GRB990907: BeppoSAX follow up and X-ray afterglow
  91. GRB990907 and 990908
  92. GRB 990712 Late Optical Decay and Host Galaxy
  93. GRB990806 BeppoSAX follow up
  94. GRB990806: BATSE Observations
  95. GRB 990806 Optical observations
  96. GRB 990806, Optical Observations
  97. GRB 990806, optical observations
  98. GRB 990806, Optical Observations
  99. GRB990806 UBVRIJHK observations
  100. GRB 990712 Optical Observations

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