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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28290 results found.

  1. GRB 121014A: Swift detection of a burst
  2. GRB 121011A: Swift/UVOT Detection
  3. GRB 121011A: misprint in GCNC 13854
  4. GRB 121011A: Fermi GBM observation
  5. GRB 121011A: Fermi-LAT detection of a burst
  6. GRB 121011A: Swift-XRT refined Analysis
  7. GRB 121011A: optical observations
  8. GRB 121011A: MASTER-Net bell light curve
  9. GRB 121011A, Swift-BAT refined analysis
  10. Swift-BAT refined analysis of the SGR 1806-20 outburst (trigger 535747)
  11. GRB 121011A: Enhanced Swift-XRT position
  12. GRB 121011A: MITSuME Okayama Optical Observation
  13. GRB 121011A: Swift detection of a burst with optical afterglow
  14. Trigger 535747: Swift detection of an outburst from SGR1806-20
  15. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  16. GRB 120927A: optical upper limit
  17. GRB 120804A: Late-time Chandra observation
  18. GRB 121001A: GROND Afterglow Confirmation
  19. GRB 121001A: Swift/UVOT Upper Limits
  20. GRB 121001A: Swift-XRT refined Analysis
  21. GRB 121001A: Enhanced Swift-XRT Position
  22. Swift Trigger 535026 is GRB 121001A: Swift-BAT refined analysis
  23. Swift Trigger 535026: Optical decay confirmation with IAC80 and BOOTES-2/TELMA.
  24. GRB 121001A: possible optical counterpart
  25. Swift Trigger 535026: Galactic Transient or possible GRB
  26. GRB 120927A: Swift/UVOT Upper Limits
  27. GRB 120927A, Swift-BAT refined analysis
  28. GRB 120927A: GROND upper limits
  29. GRB 120927A: Swift-XRT refined Analysis
  30. GRB 120927A: Enhanced Swift-XRT position
  31. GRB 120923A: JHK Observation
  32. GRB 120927A: Swift detection of a burst
  33. Further Swift-XRT observations of the GRB 120919A field.
  34. GRB 120923A: optical upper limit
  35. GRB 120921A: Fermi GBM detection of its 1000th GRB
  36. GRB 120923A: RAPTOR Early Afterglow Limits
  37. GRB 120923A: MITSuME Okayama Optical upper limits
  38. GRB 120916A Suzaku WAM observation of the prompt emission
  39. GRB 120923A: RAPTOR Limits During Gamma-Ray Emitting Interval
  40. GRB 120923A: Swift-XRT refined Analysis
  41. GRB 120923A: GROND Upper limits
  42. GRB 120922A: GROND photometric redshift
  43. GRB 120922A: Fermi GBM detection
  44. GRB 120922A: Swift/UVOT Detection
  45. GRB 120923A: Swift-BAT refined analysis
  46. GRB 120922A: Swift-BAT refined analysis
  47. GRB 120923A: Swift/UVOT Upper Limit
  48. GRB 120922A: Swift-XRT refined Analysis
  49. GRB 120922A: Swift/UVOT Observations
  50. GRB 120923A: Enhanced Swift-XRT position
  51. GRB 120922A: Enhanced Swift-XRT position
  52. GRB 120922A: TAROT La Silla observatory optical observations
  53. GRB 120923A: TAROT La Silla observatory optical observations
  54. GRB 120923A: Swift detection of a burst
  55. GRB 120922A: GROND afterglow candidate
  56. GRB 120922A: Swift detection of a burst
  57. GRB 120919B: MASTER prompt optical observations
  58. GRB 120919A: Swift/UVOT Upper Limits
  59. GRB 120919A: Swift-XRT observations
  60. GRB 120919A: Fermi GBM detection
  61. GRB 120918A: Swift-BAT refined analysis
  62. Swift trigger 534017 was not an astrophysical event
  63. GRB 120916A: Fermi GBM Observation
  64. Swift Trigger 534017 is probably not real.
  65. IPN Triangulation of long GRB 120916A
  66. Swift Trigger 533836 is a new Galactic transient
  67. GRB 120913B: Swift-BAT refined analysis
  68. GRB 120913A: Swift-BAT refined analysis
  69. GRB 120913B: REM NIR early time detection
  70. Continued Skynet/PROMPT observations of GRB120913B
  71. GRB 120913B: TAROT La Silla observatory optical photometry
  72. GRB 120913B: TAROT La Silla observatory optical detection
  73. Skynet/PROMPT observations of GRB120913B
  74. GRB 120907A: optical observations of ISON-Kislovodsk
  75. GRB 120911A: optical upper limit CrAO
  76. GRB 120911A: optical upper limit ISON-NM
  77. GRB 120911B: Fermi-LAT detection of a burst
  78. GRB 120911A: Fermi GBM observation
  79. GRB120911A: MITSuME Okayama Optical upper limits
  80. GRB 120911A: Fermi/LAT upper limit
  81. GRB 120911A: Swift/UVOT Upper Limits
  82. GRB 120911A: Swift-XRT refined Analysis
  83. GRB 120911A: Swift-BAT refined analysis
  84. GRB 120911A: Enhanced Swift-XRT position
  85. GRB 120911A: Swift-XRT observations
  86. GRB 120911A: ROTSE-III Optical Limits
  87. GRB 120911A: Swift detection of a burst
  88. GRB 120908A and GRB 120909A : Fermi/LAT upper limit
  89. GRB 120908A: Fermi GBM detection
  90. GRB 120908A: Swift Observations
  91. GRB 120909A: TAROT La Silla observatory optical observations
  92. GRB 120909A: Pi of the Sky upper limits
  93. GRB 120909A: Fermi GBM observation
  94. Konus-Wind observation of GRB 120909A
  95. GRB 120909A: Swift/UVOT Detection
  96. GRB 120909A: Swift-XRT refined Analysis
  97. GRB 120909A: Swift-BAT refined analysis
  98. GRB 120909A: Enhanced Swift-XRT position
  99. GRB 120909A: GROND detection of the afterglow
  100. Skynet/PROMPT Observations of GRB120909A

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