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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 121212A: optical observations in ISON-NM observatory
  2. GRB121212A: Swift/UVOT Detection
  3. GRB 121212A: Swift-BAT refined analysis
  4. GRB 121211A: Swift-BAT refined analysis
  5. GRB 121212A: Enhanced Swift-XRT position
  6. GRB 121212A: A long GRB detected by INTEGRAL
  7. GRB 121212A: Swift detection of a burst
  8. GRB 121211A: Swift/UVOT Detection
  9. GRB 121211A: Swift-XRT refined Analysis
  10. GRB 121211A: Enhanced Swift-XRT position
  11. GRB 121211A: Swift detection of a burst with an optical counterpart
  12. GRB 121209A: CARMA 3mm Observations
  13. GRB 121209A: EVLA Observations
  14. GRB 121209A: Swift-XRT refined Analysis
  15. GRB 121209A: Swift-BAT refined analysis
  16. GRB 121209A: Enhanced Swift-XRT position
  17. GRB 121209A: GROND optical afterglow candidate
  18. GRB 121209A: PAIRITEL NIR Observations
  19. GRB 121209A: UVOT Observation
  20. GRB 121209A: Swift detection of a burst
  21. GRB 121127A: Suzaku WAM observation of the prompt emission
  22. GRB 121128A: Optical Observations
  23. GRB 121122A: Suzaku WAM observation of the prompt emission
  24. GRB 121202A: Swift/UVOT Upper Limits
  25. GRB 121202A: Swift-XRT refined Analysis
  26. GRB 121202A: Fermi GBM observation
  27. GRB 121202A: Enhanced Swift-XRT position
  28. GRB 121202A: Swift-BAT refined analysis
  29. GRB 121202A: Swift-XRT observations
  30. GRB121202A: Swift/UVOT Observations
  31. GRB 121202A: TAROT Calern observatory optical observations
  32. GRB 121202A: Swift detection of a burst
  33. GRB 121201A: GROND afterglow observations and photometric redshift
  34. GRB 121201A: Swift/UVOT Detection
  35. GRB 121201A: Swift-XRT refined Analysis
  36. GRB 121201A: Swift-BAT refined analysis
  37. GRB 121201A: Enhanced Swift-XRT position
  38. GRB 121201A: a GRB with an optical counterpart
  39. GRB 121128A: optical observation in Mondy observatory
  40. IPN Triangulation of GRB 121127A (short/hard)
  41. GRB 121128A: optical observation in Mondy observatory
  42. GRB 121128A: Swift/UVOT Detection
  43. GRB 121128A: Swift-XRT refined Analysis
  44. GRB 121128A: Enhanced Swift-XRT position
  45. GRB 121128A: RAPTOR Detection During Gamma-Ray Emitting Interval
  46. GRB 121128A: Fermi GBM observation
  47. GRB 121128A, Swift-BAT refined analysis
  48. Konus-Wind observation of GRB 121128A
  49. GRB 121128A: Swift detection of a burst with an optical counterpart
  50. GRB 121123A: Suzaku WAM observation of the prompt emission
  51. GRB 121123A: Swift/UVOT Observations
  52. GRB 121125A: Swift/UVOT Detection
  53. IPN Triangulation of GRB 121122A (long/intense)
  54. GRB 121125A: Swift-XRT refined Analysis
  55. GRB 121125A: Enhanced Swift-XRT position
  56. GRB 121125A: Fermi GBM Observation
  57. GRB 121125A: Swift-BAT refined analysis
  58. GRB 121125A: MASTER-NET optical observations
  59. GRB 121125A: Swift detection of a burst with optical counterpart
  60. GRB 121123A: GROND observations
  61. GRB 121123A: Enhanced Swift-XRT position
  62. GRB 121123A: Swift-BAT refined analysis
  63. GRB 121123A: Swift-XRT refined Analysis
  64. GRB 121123A: optical observations
  65. GRB 121123A: Fermi GBM observation
  66. GRB 121123A: MASTER-NET optical limit
  67. GRB 121123A: Swift detection of a burst with optical counterpart
  68. GRB 121108A: optical upper limit
  69. IPN Triangulation of GRB 121118B (long/intense)
  70. GRB 121117A: GROND confirmation of the UVOT afterglow candidate
  71. Swift-BAT trigger 538575 is not astrophysical
  72. GRB 121117A: Swift/UVOT Observations
  73. GRB 121117A: Swift-XRT refined Analysis
  74. GRB 121117A: MASTER prompt optical limit
  75. GRB 121117A, Swift-BAT refined analysis
  76. GRB 121117A: ROTSE-III Optical Limits
  77. GRB 121117A: BOOTES-3 early optical upper limit
  78. GRB 121117A: Swift detection of a burst
  79. Swift trigger 538575: Magellan Observations
  80. Trigger 538084: Swift detection of XTE J1739-302
  81. GRB 121108A: Swift-XRT refined Analysis
  82. GRB 121108A: Swift/UVOT Upper Limits
  83. GRB 121108A, Swift-BAT refined analysis
  84. GRB 121108A: Enhanced Swift-XRT position
  85. GRB 121108A: Optical observations
  86. GRB 121108A: MASTER early prompt optical limit
  87. GRB 121108A: TAROT Calern observatory optical observations
  88. GRB 121108A: Swift detection of a burst
  89. GRB 121031A: Fermi GBM detection
  90. GRB 121028A: Swift/UVOT Upper Limits
  91. GRB 121031A, Early peak observed with Swift-BAT
  92. GRB 121102A: Swift/UVOT Upper Limits
  93. GRB 121031A: Swift/UVOT Upper Limits
  94. GRB 121031A: Swift-XRT refined Analysis
  95. GRB 121102A: Enhanced Swift-XRT position
  96. GRB 121031A: Enhanced Swift-XRT position
  97. GRB 121102A: Swift-XRT refined Analysis
  98. GRB 121102A: Swift-BAT refined analysis
  99. GRB 121025A: Confirmation of the X-ray afterglow
  100. GRB 121102A: Swift detection of a burst

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