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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"

26716 results found.

  1. GRB 121025A: Confirmation of the X-ray afterglow
  2. GRB 121029A Suzaku WAM observation of the prompt emission
  3. GRB 121102A : a long GRB detected by INTEGRAL
  4. GRB 121102A: Swift detection of a burst
  5. GRB 121031A: Swift detection of a burst
  6. GRB 121027A: Swift/UVOT Possible Detection
  7. GRB 121024A: SMARTS optical/IR afterglow observations
  8. GRB 121027A: GROND Confirmation of Rebrightening
  9. GRB 121029A: Fermi GBM detection
  10. GRB 121028A: RAPTOR Limits During Gamma-Ray Emitting Interval
  11. GRB 121027A: MASTER early prompt optical limit
  12. GRB 121027A: Swift-XRT refined Analysis
  13. GRB 121028A: Swift-XRT refined Analysis
  14. GRB 121028A: Enhanced Swift-XRT position
  15. GRB 121028A: Swift-BAT refined analysis
  16. GRB 121027A: Enhanced Swift-XRT position
  17. GRB 121028A: MITSuME Okayama Optical upper limits
  18. GRB 121028A: Faulkes Telescope North observations
  19. GRB 121028A: Swift detection of a burst
  20. GRB 121011A: optical observations
  21. GRB 121027A: nIR afterglow candidate with AAT
  22. GRB 121025A: Swift-XRT observation
  23. GRB 121027A: Swift detection of a burst
  24. GRB 121024A: optical observations
  25. GRB 121024A: Swift/UVOT Observations
  26. GRB 121024A: Swift-BAT refined analysis
  27. GRB 121024A: GMG optical observation
  28. GRB 121024A: MITSuME Ishigakijima upper limits
  29. GRB 121024A: MITSuME Okayama Optical upper limits
  30. GRB 121024A: Enhanced Swift-XRT position
  31. GRB 121024A: PAIRITEL NIR Detection
  32. GRB 121024A: Swift-XRT refined Analysis
  33. GRB 121024A: GROND Detection of the Optical/NIR Afterglow
  34. Skynet PROMPT/Dolomiti observations of GRB121024A
  35. GRB 121024A: TAROT Calern observatory optical detection of a bright counterpart
  36. GRB 121024A: Swift detection of a burst with an optical counterpart
  37. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  38. GRB 121017A: Swift/UVOT Upper Limits
  39. GRB 121017A: Swift-XRT refined Analysis
  40. GRB 121017A: GROND Observations
  41. GRB 121017A: Enhanced Swift-XRT position
  42. GRB 121017A: 1.23m CAHA R-band observations
  43. GRB 121017A optical observations
  44. GRB 121017A: BOOTES-2/TELMA observations
  45. GRB 121017A: Swift detection of a burst
  46. GRB 121011B: Suzaku WAM observation of the prompt emission
  47. GRB 121011A Suzaku WAM observation of the prompt emission
  48. GRB 121012A: Fermi GBM detection
  49. GRB 121014A: Swift detection of a burst
  50. GRB 121011A: Swift/UVOT Detection
  51. GRB 121011A: misprint in GCNC 13854
  52. GRB 121011A: Fermi GBM observation
  53. GRB 121011A: Fermi-LAT detection of a burst
  54. GRB 121011A: Swift-XRT refined Analysis
  55. GRB 121011A: optical observations
  56. GRB 121011A: MASTER-Net bell light curve
  57. GRB 121011A: Enhanced Swift-XRT position
  58. GRB121011A : Xinglong TNT optical observation
  59. GRB 121011A: MITSuME Okayama Optical Observation
  60. GRB 121011A: Swift detection of a burst with optical afterglow
  61. Trigger 535747: Swift detection of an outburst from SGR1806-20
  62. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  63. GRB 120927A: optical upper limit
  64. GRB 120804A: Late-time Chandra observation
  65. GRB 121001A: GROND Afterglow Confirmation
  66. GRB 121001A: Swift/UVOT Upper Limits
  67. GRB 121001A: Swift-XRT refined Analysis
  68. GRB 121001A: Enhanced Swift-XRT Position
  69. Swift Trigger 535026 is GRB 121001A: Swift-BAT refined analysis
  70. Swift Trigger 535026: Optical decay confirmation with IAC80 and BOOTES-2/TELMA.
  71. GRB 121001A: possible optical counterpart
  72. Swift Trigger 535026: Galactic Transient or possible GRB
  73. GRB 120927A: Swift/UVOT Upper Limits
  74. GRB 120927A: GROND upper limits
  75. GRB 120927A: Swift-XRT refined Analysis
  76. GRB 120927A: Enhanced Swift-XRT position
  77. GRB 120923A: JHK Observation
  78. GRB 120927A: Swift detection of a burst
  79. Further Swift-XRT observations of the GRB 120919A field.
  80. GRB 120923A: optical upper limit
  81. GRB 120921A: Fermi GBM detection of its 1000th GRB
  82. GRB 120923A: RAPTOR Early Afterglow Limits
  83. GRB 120923A: MITSuME Okayama Optical upper limits
  84. GRB 120916A Suzaku WAM observation of the prompt emission
  85. GRB 120923A: RAPTOR Limits During Gamma-Ray Emitting Interval
  86. GRB 120923A: Swift-XRT refined Analysis
  87. GRB 120923A: GROND Upper limits
  88. GRB 120922A: GROND photometric redshift
  89. GRB 120922A: Fermi GBM detection
  90. GRB 120922A: Swift/UVOT Detection
  91. GRB 120923A: Swift/UVOT Upper Limit
  92. GRB 120922A: Swift-XRT refined Analysis
  93. GRB 120923A: Enhanced Swift-XRT position
  94. GRB 120922A: Enhanced Swift-XRT position
  95. GRB 120922A: TAROT La Silla observatory optical observations
  96. GRB 120923A: TAROT La Silla observatory optical observations
  97. GRB 120923A: Swift detection of a burst
  98. GRB 120922A: GROND afterglow candidate
  99. GRB 120922A: Swift detection of a burst
  100. GRB 120919B: MASTER prompt optical observations

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