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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"

27454 results found.

  1. GRB 130102A: Swift detection of a burst
  2. Swift Trigger 544381 is a noise event
  3. GRB 121229A: Swift-XRT refined Analysis
  4. GRB 121229A, Swift-BAT refined analysis
  5. GRB 121229A: Swift/UVOT Upper Limits
  6. GRB 121229A: VLT/X-shooter redshift
  7. Swift Trigger 544381 is unlikely to be a GRB
  8. GRB 121229A: MAXI/GSC detection
  9. GRB 121229A: GROND detection of the afterglow
  10. GRB 121229A: Swift detection of a burst
  11. GRB 121226A: Swift/UVOT Upper Limits
  12. GRB 121226A: Swift-XRT refined Analysis
  13. GRB 121226A, Swift-BAT refined analysis
  14. GRB 121226A: NOT optical upper limit
  15. GRB 121226A: Optical Observations
  16. GRB 121226A: Zadko observatory - Gingin optical observations
  17. GRB 121226A: BOOTES-4/MET optical observations
  18. GRB 121226A: Swift detection of a burst
  19. IPN Triangulation of GRB 121225B
  20. GRB 121225B: Fermi GBM observation
  21. GRB 121225B: Fermi LAT Detection
  22. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  23. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  24. GRB 121217A: Swift-BAT refined analysis
  25. GRB 121217A theoretical estimate of redshift and of supernova occurrence
  26. GRB 121217A: Fermi GBM observation
  27. GRB 121217A: Swift-XRT refined Analysis
  28. GRB 121217A: Swift/UVOT Detection
  29. GRB 121217A: GROND Detection of the Afterglow
  30. GRB 121217A: Swift detection of a burst
  31. GRB 121209A: Swift/UVOT Upper Limits
  32. GRB 121212A: LOAO IzY Observation
  33. GRB 121209A: MAXI/GSC detection
  34. GRB121212A: NOT optical imaging
  35. GRB 121209A: Early CARMA Observations
  36. GRB 121211A: Continued RATIR Optical and NIR Observations, Fading
  37. GRB 121211A: Fermi GBM observation
  38. GRB 121211A: RATIR Optical and NIR Observations
  39. GRB 121212A: RAPTOR Limits During Gamma-Ray Emitting Interval
  40. GRB 121211A: RAPTOR Limits During Gamma-Ray Emitting Interval
  41. GRB 121212A: PAIRITEL NIR Observations
  42. GRB 121212A: Swift-XRT refined Analysis
  43. GRB 121212A: P60 Observations
  44. GRB 121212A: optical observations in ISON-NM observatory
  45. GRB121212A: Swift/UVOT Detection
  46. GRB 121212A: Swift-BAT refined analysis
  47. GRB 121211A: Swift-BAT refined analysis
  48. GRB 121212A: Swift detection of a burst
  49. GRB 121211A: Swift/UVOT Detection
  50. GRB 121211A: Swift-XRT refined Analysis
  51. GRB 121211A: Keck/LRIS redshift
  52. GRB 121211A - Faulkes Telescope North afterglow confirmation
  53. GRB 121211A: Swift detection of a burst with an optical counterpart
  54. GRB 121209A: Swift-XRT refined Analysis
  55. GRB 121209A: Swift-BAT refined analysis
  56. GRB121209A: RATIR Optical and NIR Upper Limits
  57. GRB 121209A: GROND optical afterglow candidate
  58. GRB 121209A: Gemini-South imaging
  59. GRB 121209A: PAIRITEL NIR Observations
  60. GRB 121209A: UVOT Observation
  61. GRB 121209A: Swift detection of a burst
  62. GRB 121128A: Optical Observations
  63. GRB 121202A: Swift/UVOT Upper Limits
  64. GRB 121202A: Swift-XRT refined Analysis
  65. GRB 121202A: Fermi GBM observation
  66. GRB 121202A: Swift-BAT refined analysis
  67. GRB 121202A: Swift-XRT observations
  68. GRB121202A: Swift/UVOT Observations
  69. GRB 121202A: TAROT Calern observatory optical observations
  70. GRB 121202A: Swift detection of a burst
  71. GRB 121201A: GROND afterglow observations and photometric redshift
  72. GRB 121201A: Swift/UVOT Detection
  73. GRB 121201A: Swift-XRT refined Analysis
  74. GRB 121201A: Swift-BAT refined analysis
  75. GRB 121201A: a GRB with an optical counterpart
  76. IPN Triangulation of GRB 121127A (short/hard)
  77. GRB 121128A: Swift/UVOT Detection
  78. GRB 121128A: Swift-XRT refined Analysis
  79. GRB 121122A: Fermi GBM observation
  80. GRB 121128A: RAPTOR Detection During Gamma-Ray Emitting Interval
  81. GRB 121128A: Fermi GBM observation
  82. GRB 121128A, Swift-BAT refined analysis
  83. Konus-Wind observation of GRB 121128A
  84. GRB 121128A: FTN optical afterglow confirmation
  85. GRB 121128A: Swift detection of a burst with an optical counterpart
  86. GRB 121117A: Terskol obseravtions
  87. GRB 121123A: Swift/UVOT Observations
  88. GRB 121125A: Swift/UVOT Detection
  89. IPN Triangulation of GRB 121122A (long/intense)
  90. GRB 121125A: Swift-XRT refined Analysis
  91. GRB 121125A: Fermi GBM Observation
  92. GRB 121125A: Swift-BAT refined analysis
  93. GRB 121125A: LOAO Observation
  94. GRB 121125A: MASTER-NET optical observations
  95. GRB 121125A: Swift detection of a burst with optical counterpart
  96. GRB 121123A: GROND observations
  97. GRB 121123A: Swift-BAT refined analysis
  98. GRB 121123A: Swift-XRT refined Analysis
  99. GRB 121123A: optical observations
  100. GRB 121123A: NOT optical observations

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