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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"

37704 results found.

  1. GRB 121011A: NOT redshift retraction
  2. GRB 121011A: misprint in GCNC 13854
  3. GRB 121011A: Fermi GBM observation
  4. GRB 121011A: Fermi-LAT detection of a burst
  5. GRB 121011A: Swift-XRT refined Analysis
  6. GRB 121011A: NOT optical observations
  7. GRB 121011A: optical observations
  8. GRB 121011A: MASTER-Net bell light curve
  9. GRB 121011A: TNG optical observations
  10. GRB 121011A, Swift-BAT refined analysis
  11. GRB 121011A: Enhanced Swift-XRT position
  12. Planned XMM-Newton and IRAM observation of GRB 121011A
  13. GRB 121011A: MASTER-Net early OT light curve
  14. GRB 121011A: MITSuME Okayama Optical Observation
  15. GRB 121011A: Swift detection of a burst with optical afterglow
  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. GRB 121001A: MASTER optical observations
  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 120923A: Correction to GCN 13823
  31. GRB 120927A: Enhanced Swift-XRT position
  32. GRB 120923A: JHK Observation
  33. GRB 120927A: Swift detection of a burst
  34. Further Swift-XRT observations of the GRB 120919A field.
  35. GRB 120923A: optical upper limit
  36. GRB 120921A: Fermi GBM detection of its 1000th GRB
  37. GRB 120923A: RAPTOR Early Afterglow Limits
  38. GRB 120923A: MITSuME Okayama Optical upper limits
  39. GRB 120916A Suzaku WAM observation of the prompt emission
  40. GRB 120923A: RAPTOR Limits During Gamma-Ray Emitting Interval
  41. GRB 120923A: CARMA Observations
  42. GRB 120923A: EVLA Observations
  43. GRB 120923A: Swift-XRT refined Analysis
  44. GRB 120923A: GROND Upper limits
  45. GRB 120922A: GROND photometric redshift
  46. GRB 120922A: Fermi GBM detection
  47. GRB 120922A: Swift/UVOT Detection
  48. GRB 120923A: Swift-BAT refined analysis
  49. GRB 120922A: Swift-BAT refined analysis
  50. GRB 120923A: Swift/UVOT Upper Limit
  51. GRB 120922A: Swift-XRT refined Analysis
  52. GRB 120922A: Swift/UVOT Observations
  53. GRB 120923A: Gemini afterglow detection, high-z candidate
  54. GRB 120923A: Enhanced Swift-XRT position
  55. GRB 120922A: Enhanced Swift-XRT position
  56. GRB 120922A: TAROT La Silla observatory optical observations
  57. GRB 120923A: TAROT La Silla observatory optical observations
  58. GRB 120923A: ROTSE-III Optical Limits
  59. GRB 120923A: Swift detection of a burst
  60. GRB 120922A: GROND afterglow candidate
  61. GRB 120922A: Prompt enhanced Swift-XRT position
  62. GRB 120922A: Swift detection of a burst
  63. GRB 120919B: MASTER prompt optical observations
  64. GRB 120919A: Swift/UVOT Upper Limits
  65. GRB 120919A: Swift-XRT observations
  66. Konus-Wind observation of GRB 120919B
  67. IPN Triangulation of long GRB 120919B
  68. Konus-Wind observation of GRB 120919A
  69. IPN Triangulation of long GRB 120919A
  70. GRB 120919A: Fermi GBM detection
  71. GRB 120918A: Swift-BAT refined analysis
  72. GRB 120916A: Fermi GBM Observation
  73. Konus-Wind observation of GRB 120916A
  74. GRB 120918A: Swift detection of a burst
  75. IPN Triangulation of long GRB 120916A
  76. GRB 120916A: Fermi-LAT detection of a burst
  77. Corrections to the Fermi-LAT upper limits for GRB 120807A, 120908A, 120909A, and 120911A
  78. GRB 120913B: Fermi GBM observation
  79. GRB 120913B: Swift-BAT refined analysis
  80. GRB 120913A: Fermi GBM observation
  81. GRB 120913B: FRAM early follow up and detection
  82. GRB 120913A: Swift-BAT refined analysis
  83. GRB 120913B: REM NIR early time detection
  84. Continued Skynet/PROMPT observations of GRB120913B
  85. GRB 120913B: TAROT La Silla observatory optical photometry
  86. GRB 120913B: TAROT La Silla observatory optical detection
  87. GRB 120913B: Swift detection of a burst
  88. GRB 120913A: Swift detection of a burst
  89. GRB 120907A: optical observations of ISON-Kislovodsk
  90. GRB 120911A: optical upper limit CrAO
  91. GRB 120911A: optical upper limit ISON-NM
  92. Konus-Wind observation of GRB 120911B
  93. GRB 120911B: Fermi GBM observation
  94. GRB 120911B: Fermi-LAT detection of a burst
  95. IPN Triangulation of GRB 120911B (long/bright)
  96. GRB 120911A: Fermi GBM observation
  97. GRB120911A: MITSuME Okayama Optical upper limits
  98. GRB 120911A: Fermi/LAT upper limit
  99. GRB 120911A: Swift/UVOT Upper Limits
  100. GRB 120911A: Swift-XRT refined Analysis

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