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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"
  1. Swift Trigger 535026: Galactic Transient or possible GRB
  2. GRB 120927A: Swift/UVOT Upper Limits
  3. GRB 120927A, Swift-BAT refined analysis
  4. GRB 120927A: GROND upper limits
  5. GRB 120927A: Swift-XRT refined Analysis
  6. GRB 120923A: Correction to GCN 13823
  7. GRB 120927A: Enhanced Swift-XRT position
  8. GRB 120923A: JHK Observation
  9. GRB 120927A: Swift detection of a burst
  10. Further Swift-XRT observations of the GRB 120919A field.
  11. GRB 120923A: optical upper limit
  12. GRB 120921A: Fermi GBM detection of its 1000th GRB
  13. GRB 120923A: RAPTOR Early Afterglow Limits
  14. GRB 120923A: MITSuME Okayama Optical upper limits
  15. GRB 120916A Suzaku WAM observation of the prompt emission
  16. GRB 120923A: RAPTOR Limits During Gamma-Ray Emitting Interval
  17. GRB 120923A: CARMA Observations
  18. GRB 120923A: EVLA Observations
  19. GRB 120923A: Swift-XRT refined Analysis
  20. GRB 120923A: GROND Upper limits
  21. GRB 120922A: GROND photometric redshift
  22. GRB 120922A: Fermi GBM detection
  23. GRB 120922A: Swift/UVOT Detection
  24. GRB 120923A: Swift-BAT refined analysis
  25. GRB 120922A: Swift-BAT refined analysis
  26. GRB 120923A: Swift/UVOT Upper Limit
  27. GRB 120922A: Swift-XRT refined Analysis
  28. GRB 120922A: Swift/UVOT Observations
  29. GRB 120923A: Gemini afterglow detection, high-z candidate
  30. GRB 120923A: Enhanced Swift-XRT position
  31. GRB 120922A: Enhanced Swift-XRT position
  32. GRB 120922A: TAROT La Silla observatory optical observations
  33. GRB 120923A: TAROT La Silla observatory optical observations
  34. GRB 120923A: ROTSE-III Optical Limits
  35. GRB 120923A: Swift detection of a burst
  36. GRB 120922A: GROND afterglow candidate
  37. GRB 120922A: Prompt enhanced Swift-XRT position
  38. GRB 120922A: Swift detection of a burst
  39. GRB 120919B: MASTER prompt optical observations
  40. GRB 120919A: Swift/UVOT Upper Limits
  41. GRB 120919A: Swift-XRT observations
  42. Konus-Wind observation of GRB 120919B
  43. IPN Triangulation of long GRB 120919B
  44. Konus-Wind observation of GRB 120919A
  45. IPN Triangulation of long GRB 120919A
  46. GRB 120919A: Fermi GBM detection
  47. GRB 120918A: Swift-BAT refined analysis
  48. Swift trigger 534017 was not an astrophysical event
  49. GRB 120916A: Fermi GBM Observation
  50. Konus-Wind observation of GRB 120916A
  51. Swift Trigger 534017 is probably not real.
  52. GRB 120918A: Swift detection of a burst
  53. IPN Triangulation of long GRB 120916A
  54. GRB 120916A: Fermi-LAT detection of a burst
  55. Corrections to the Fermi-LAT upper limits for GRB 120807A, 120908A, 120909A, and 120911A
  56. Swift Transient Swift J174510.8-262411: Swift-BAT refined analysis
  57. Swift Trigger 533836 is a new Galactic transient
  58. GRB 120913B: Fermi GBM observation
  59. GRB 120913B: Swift-BAT refined analysis
  60. GRB 120913A: Fermi GBM observation
  61. GRB 120913B: FRAM early follow up and detection
  62. GRB 120913A: Swift-BAT refined analysis
  63. GRB 120913B: REM NIR early time detection
  64. Continued Skynet/PROMPT observations of GRB120913B
  65. GRB 120913B: TAROT La Silla observatory optical photometry
  66. GRB 120913B: TAROT La Silla observatory optical detection
  67. Skynet/PROMPT observations of GRB120913B
  68. GRB 120913B: Swift detection of a burst
  69. GRB 120913A: Swift detection of a burst
  70. GRB 120907A: optical observations of ISON-Kislovodsk
  71. GRB 120911A: optical upper limit CrAO
  72. GRB 120911A: optical upper limit ISON-NM
  73. Konus-Wind observation of GRB 120911B
  74. GRB 120911B: Fermi GBM observation
  75. GRB 120911B: Fermi-LAT detection of a burst
  76. IPN Triangulation of GRB 120911B (long/bright)
  77. GRB 120911A: Fermi GBM observation
  78. GRB120911A: MITSuME Okayama Optical upper limits
  79. GRB 120911A: Fermi/LAT upper limit
  80. GRB 120911A: Swift/UVOT Upper Limits
  81. GRB 120911A: Swift-XRT refined Analysis
  82. GRB 120911A: Swift-BAT refined analysis
  83. GRB 120911A: Enhanced Swift-XRT position
  84. GRB 120911A: Faulkes Telescope North observations
  85. GRB 120911A: Swift-XRT observations
  86. GRB 120911A: ROTSE-III Optical Limits
  87. GRB 120911A: Swift detection of a burst
  88. GRB 120907A: SMA upper limits
  89. GRB 120908A and GRB 120909A : Fermi/LAT upper limit
  90. GRB 120908A: Fermi GBM detection
  91. GRB 120908A: Swift Observations
  92. GRB 120909A: TAROT La Silla observatory optical observations
  93. GRB 120909A: Pi of the Sky upper limits
  94. GRB 120909A: Fermi GBM observation
  95. Konus-Wind observation of GRB 120909A
  96. GRB 120909A: Swift/UVOT Detection
  97. GRB 120909A: Swift-XRT refined Analysis
  98. GRB 120909A: Swift-BAT refined analysis
  99. GRB 120909A: Enhanced Swift-XRT position
  100. GRB 120908A: MAXI/GSC detection

Advanced

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