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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"

18435 results found.

  1. GRB 100316B: Enhanced Swift-XRT position
  2. GRB 100316A: Swift-BAT refined analysis
  3. GRB 100316B: Swift-BAT refined analysis
  4. GRB100316A: Swift/UVOT Upper Limits
  5. Trigger 416140 is almost certainly not a GRB
  6. GRB 100316D: Swift detection of a burst
  7. GRB 100316B: Skynet/PROMPT Observations of Fading
  8. GRB 100316B: GROND Detection of the Optical/NIR Afterglow Candidate
  9. GRB 100316C: Swift detection of a burst
  10. GRB 100316A: Enhanced Swift-XRT position
  11. GRB 100316B: Swift detection of a burst with optical counterpart
  12. GRB 100316A: Swift/UVOT Observations
  13. GRB 100316A: Swift-XRT detection
  14. GRB 100316A: Swift detection of a burst
  15. GRB 100305A, Swift-BAT refined analysis
  16. GRB 100305A: Swift/UVOT Upper Limits
  17. GRB 100305A: Swift-XRT refined analysis
  18. GRB 100305A Optical Observations
  19. GRB 100305A: Enhanced Swift-XRT position
  20. GRB 100305A: PAIRITEL NIR Upper Limits
  21. GRB 100305A: Swift detection of a burst
  22. GRB 100302A: Swift/UVOT Upper Limits
  23. GRB 100302A: Swift-XRT refined analysis
  24. GRB 100302A: Optical observations at Crni Vrh
  25. GRB 100302A: MASTER-Net optical alert observations
  26. GRB 100302A, Swift-BAT refined analysis
  27. GRB 100302A: Enhanced Swift-XRT position
  28. GRB 100302A: Skynet/DAO Observations
  29. GRB 100302A: Swift detection of a burst
  30. GRB 100206A: optical observations in CrAO
  31. GRB 100206A: optical observations in Terskol
  32. GRB 100219A: optical observations
  33. GRB 100224A SHB found in ground analysis of BAT data
  34. Swift Triggers 413744 and 413745 are not GRBs
  35. GRB
  36. GRB 100219A: XRT refined analysis
  37. GRB 100216A: Swift/UVOT Observations
  38. GRB 100219A: GROND observations
  39. GRB 100219A: Enhanced Swift-XRT position
  40. GRB 100219A: Swift/UVOT Detection of the Optical Afterglow
  41. GRB 100216A: XRT Refined Analysis
  42. GRB 100219A: Swift-BAT refined analysis
  43. GRB 100219A: Swift/UVOT Detection of a Source near the XRT Position
  44. GRB 100219A: Swift detection of a burst
  45. GRB 100216A Short, hard GRB detected in ground analysis of Swift-BAT data
  46. GRB 100213A: Swift-BAT lag analysis indicates probably SHB
  47. GRB 100213B: GRT Optical Observation
  48. GRB 100213A: GRT Optical Observation
  49. GRB 100213A: Swift-BAT refined analysis
  50. GRB 100213B: Enhanced Swift-XRT position
  51. GRB 100213B: Swift/UVOT Upper Limits
  52. GRB 100213A: Swift/UVOT Upper Limits
  53. GRB 100213B: PAIRITEL NIR Upper Limits
  54. GRB 100213A: Enhanced Swift-XRT position
  55. GRB 100213B: Swift-BAT refined analysis
  56. GRB 100213B: Swift XRT refined analysis
  57. GRB 100213A: Swift XRT refined analysis
  58. GRB 100213B: Swift detection of a burst
  59. GRB 100213A: Swift detection of a burst
  60. Swift/UVOT observations of GRB100212A - correction of the name of the burst
  61. Swift/UVOT observations of GRB120212A
  62. GRB 100212A: Fermi GBM detection
  63. GRB 100212A: Swift XRT refined analysis
  64. GRB 100212A: Swift-BAT refined analysis
  65. GRB 100212A: Enhanced Swift-XRT position
  66. GRB 100212A: Swift detection of a burst
  67. GRB 100206A: GROND upper limits
  68. GRB 100206A: Swift/UVOT Upper Limits
  69. GRB 100206A: MASTER-Net optical alert observations
  70. GRB 100206A, RIMOTS optical upper limits
  71. GRB 100206A: optical observations from Southern Spain
  72. GRB 100205A: GROND upper limits
  73. GRB 100206A: Swift-XRT refined analysis
  74. GRB 100206A: Fermi GBM observation
  75. GRB 100206A: Swift-BAT refined analysis
  76. GRB 100206A: Enhanced Swift-XRT position
  77. GRB 100206A: Swift detection of a short hard burst
  78. GRB 100205A: Swift-BAT refined analysis
  79. GRB 100205A: Swift UVOT upper limits
  80. GRB 100205A: Swift XRT refined analysis
  81. GRB 100203A: Swift XRT and UVOT refined analyses
  82. GRB 100205A: Enhanced Swift-XRT position
  83. GRB 100205A: Swift detection of a burst
  84. GRB 100203A Detected in Ground Analysis of BAT Data
  85. GRB 100119A: Suzaku WAM observation of the prompt emission
  86. Konus-Wind observation of GRB 100119A
  87. GRB 100115A: Swift-XRT refined analysis
  88. GRB 100119A: Swift-BAT refined analysis
  89. GRB 100119A: Swift detection of a burst
  90. GRB 100117A: Fermi GBM detection
  91. Swift/UVOT refined analysis of GRB100117A
  92. GRB 100117A: Optical object inside the revised XRT error circle
  93. GRB 100117A: Swift-XRT refined analysis
  94. GRB 100117A: Swift-BAT refined analysis
  95. GRB 100117A: Swift detection of a short hard burst
  96. GRB 100115A: Enhanced Swift-XRT position
  97. GRB 100116A: Fermi LAT detection
  98. NOT observation of GRB100115A localization
  99. GRB 100115A: SARA Afterglow Candidate
  100. GRB 100115A: Swift/UVOT Upper Limits

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