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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"

19531 results found.

  1. GRB 081228: Swift-XRT Team refined analysis
  2. GRB 081228: detection by GROND
  3. GRB 081228: Enhanced Swift-XRT position
  4. GRB 081228: TAROT Calern observatory optical observations
  5. GRB 081228: Swift detection of a burst
  6. GRB 081226B: Swift XRT and UVOT upper limits
  7. GRB 081226: Swift-XRT refined analysis
  8. GRB 081226A: Swift UVOT Upper Limits
  9. GRB 081226A: Swift-BAT refined analysis
  10. GRB 081226: ROTSE-III Optical Limits
  11. GRB 081226: Swift detection of a possible short-hard burst
  12. GRB 081224: Swift-XRT observation
  13. Konus-Wind observation of GRB 081222
  14. GRB 081221: GROND observations
  15. GRB 081222:Optical afterglow observation
  16. GRB 081222: Fermi GBM observation
  17. GRB081222: Swift/UVOT further observations
  18. GRB 081221: Probable host galaxy in Keck imaging
  19. GRB 081222, Swift-BAT refined analysis
  20. GRB 081221, Swift-BAT refined analysis
  21. GRB081222 optical limit by "Pi of the Sky"
  22. GRB 081222: Swift XRT refined analysis
  23. GRB081221: Fermi GBM observation
  24. Swift/UVOT observations of GRB 081221
  25. IPN triangulation of bright GRB 081215A
  26. GRB 081221: Swift-XRT Refined Analysis
  27. GRB 081221: pseudo-redshift (pz=0.7) from the spectral parameters of the prompt emission
  28. GRB081222, optical observation
  29. GRB081222: Swift/UVOT detection of an optical afterglow
  30. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  31. GRB 081222: Swift detection of a burst with a bright optical afterglow
  32. GRB 081221: Enhanced Swift-XRT position
  33. GRB 081221: Swift detection of a burst
  34. Modification of Swift/UVOT response to bright GRBs
  35. GRB 081211B: Further Swift-XRT analysis
  36. GRB 081211B - possibly a short burst with extended emission
  37. Possible GRB 081211B: Swift/UVOT Upper Limits
  38. GRB 081210: optical observations
  39. Possible GRB 081211B - Swift-XRT analysis
  40. GRB 081211B(?): Possible burst detection from Swift-BAT slew data
  41. GRB 081211: Swift-BAT refined analysis
  42. GRB 081211: Swift XRT refined analysis
  43. GRB 081211: Swift/UVOT detection of an optical afterglow
  44. GRB 081211: Enhanced Swift-XRT position
  45. GRB 081210: Swift/UVOT refined analysis
  46. GRB 081211: Swift detection of a burst
  47. GRB 081210: Swift-XRT refined analysis
  48. GRB 081210: Enhanced Swift-XRT position
  49. GRB 081210: Swift-BAT refined analysis
  50. GRB 081210: Swift detection of a burst with optical afterglow
  51. IPN triangulation of short hard GRB 081209
  52. Radio observation of GRB 081121 with ATCA
  53. GRB 081203B: Suzaku WAM observation of the prompt emission
  54. Radio observation of GRB 081029 with ATCA
  55. Radio observation of GRB 081008 with ATCA
  56. GRB081203A: Ashra-1 observation of early optical and VHE-neutrino emission
  57. GRB 081128: optical observation in CrAO
  58. GRB 081128: Optical afterglow observations
  59. GRB 081204: GROND Observations
  60. GRB 081204: Swift/UVOT Upper Limits
  61. GRB 081204: Swift XRT afterglow confirmation
  62. GRB 081204: Swift XRT afterglow candidate
  63. Swift-XRT observations of GRB 081203B
  64. Konus-Wind observation of GRB 081203A
  65. Konus-Wind observation of GRB 081203B
  66. GRB081203A: Swift-XRT refined analysis
  67. GRB 081203B: optical observations
  68. Swift/UVOT detection of GRB081203B
  69. GRB 081203B: Swift-XRT candidate afterglow.
  70. GRB 081203A: optical observations
  71. Swift UVOT observations of GRB 081203A
  72. GRB 081203B: Naming correction for burst detected in Swift-BAT slew data
  73. GRB081203A: Swift/UVOT grism redshift
  74. GRB 081203A: Burst detection from Swift-BAT slew data
  75. GRB 081203A: Swift-BAT refined analysis
  76. GRB 081203: Enhanced Swift-XRT position
  77. GRB081203: optical observation
  78. GRB 081203: Swift detection of a burst with a bright optical counterpart
  79. GRB 081128: optical observation
  80. Swift Trigger 335971: Swift/UVOT Observations
  81. GRB 081126: Fermi GBM detection
  82. Swift Trigger 335971 is probably not a real source
  83. Trigger 335971: Swift possible detection of a burst
  84. GRB081128: Swift/UVOT Upper Limits
  85. GRB 081128: Swift-XRT refined analysis
  86. GRB081128: optical observations
  87. GRB 081128: Swift-BAT refined analysis
  88. GRB 081128: Enhanced Swift-XRT position
  89. GRB 081128: Swift detection of a burst
  90. GRB 081126: Swift observations continuing
  91. GRB081126: Afterglow photometry from Crni Vrh
  92. GRB 081126: GRT Optical Observation
  93. GRB 081127: Swift/UVOT Upper Limits
  94. GRB 081127: Swift-XRT refined analysis
  95. GRB 081127: Enhanced Swift-XRT position
  96. GRB 081126: Confirmation of the Optical Afterglow
  97. GRB 081127: Swift-BAT refined analysis
  98. GRB 081126: Swift-XRT refined analysis
  99. GRB 081127: Swift detection of a burst
  100. GRB 081126: Swift/UVOT Observations

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