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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"

27319 results found.

  1. GRB000301C, optical R-band observations
  2. GRB 000301C Optical Observations
  3. GRB 000301C: K' Observations
  4. GRB000301C OT candidate optical observations
  5. GRB000301C - Host galaxy not detected in R (?)
  6. Optical observations of GRB000301c
  7. GRB000301C, Radio observations
  8. GRB000301C, Radio observations
  9. GRB000301C, near-infrared observations (JHK' imaging)
  10. GRB 000301c near-IR observations
  11. GRB 000301C, UBVRI field photometry
  12. GRB 000301C: OT confirmed
  13. GRB000301c optical observations
  14. GRB000301C, optical observations
  15. GRB000301C
  16. GRB 000301C : Optical Candidate
  17. GRB000301C: RXTE/ASM and IPN localizations
  18. GRB000226 [IPN Position]
  19. HST Observations of GRB 990712
  20. GRB 000214 near-IR observations
  21. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  22. GRB000210, Radio Observations
  23. GRB 000115, BVRI field photometry
  24. GRB000214: BeppoSAX GRBM and WFC Detection
  25. Optical observations of GRB000210
  26. GRB000210 X-ray afterglow
  27. GRB000214: X-ray afterglow candidate
  28. GRB000214 refined BeppoSAX-WFC position
  29. GRB 000210: BATSE Observations
  30. Optical observations of the Chandra X-ray source for GRB000210
  31. GRB000210, Radio Observations
  32. IPN triangulation of GRB000210
  33. GRB000210: possible afterglow detection with BeppoSAX NFI
  34. GRB000201, Radio Observations
  35. GRB000210: BeppoSAX GRBM and WFC Detection
  36. SAX_WFC_GRB_NOTICE
  37. SAX_WFC_GRB_NOTICE
  38. GRB000201 Optical Observations
  39. GRB 000201: TAROT optical observations
  40. GRB 991208, radio observations
  41. BATSE+IPN location of GRB000131
  42. IPN localization of GRB000131
  43. GRB 000126, optical observations
  44. BATSE Observations of GRB000115
  45. Second RXTE Observation of GRB 000115
  46. GRB991216, UBVRIJHK field photometry
  47. GCN resumes full operations
  48. GRB 991216 VLBA Observations
  49. GRB 991216: J band spectrophotometry
  50. GRB 991216: Detection of the Host and/or Absorber Galaxy
  51. IPN localization of GRB991226
  52. GRB 991216 RXTE ASM Observations
  53. GRB 991216: Updated BATSE parameters
  54. GRB 991217 (SAX J2303.2+0015) Optical observations
  55. Chandra observation of the X-ray afterglow of GRB991216
  56. GRB 991216, optical observations
  57. GRB 991216 Optical spectroscopy/imaging
  58. SAX J2303.2+0015 Optical observations
  59. IR observations of GRB991216
  60. GRB 991217 (SAX J2303.2+0015) Optical observations
  61. GRB991216 Optical and infrared observations of Beethoven Burst
  62. GRB 991216 Radio Observations
  63. GRB 991208 Keck Spectroscopy
  64. GRB 991208 Infrared Detection
  65. GRB991216
  66. GRB 991216--Summary of RXTE Observations
  67. GRB 991216 Optical Observations
  68. GRB 991216, optical observations
  69. GRB 991208 SAO-RAS Spectroscopy
  70. SAX J2303.2+0015: an x-ray/GRB?
  71. GRB 991216, Optical Transient
  72. GRB991216 ('Beethoven Burst') B, R, and K Observations
  73. GRB991216, infrared observations
  74. GRB 991208 optical observations
  75. GRB 991216 Optical Observation
  76. GRB 991216: Extremely bright BATSE burst
  77. R-band Observations of GRB991208 at TNG
  78. GRB991208, optical observations
  79. GRB 991208, Optical Observation
  80. GRB991208, optical observations
  81. GRB 991208 optical observations
  82. Optical Observations of GRB991105
  83. GRB991106: BeppoSAX/BATSE results
  84. GRB991106, near-infrared observations
  85. BeppoSAX NFI Observation of GRB991106
  86. GRB 991106, radio observations
  87. GRB991106: the first BeppoSAX short GRB detection?
  88. GRB 991105: BATSE Observations
  89. GRB 991106 Optical Observations
  90. GRB991106, optical observation at SAO-RAS
  91. GRB 991106, LOTIS Optical Observations
  92. GRB991105: SAX-GRBM/-WFC detection
  93. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  94. GRB 991014, Optical Observations
  95. GRB 991014 - BeppoSAX NFI observations
  96. GRB 991014, radio observations
  97. GRB 991014, Optical Observations
  98. GRB 991014, optical observations
  99. GRB 990915 optical observations
  100. Optical Observations of GRB990907

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