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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').

18348 results found.

  1. Refined analysis of the SWIFT J1626.6-5156
  2. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  3. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  4. GRB 051211B: optical afterglow
  5. Swift detection of an RS CVn flare star
  6. Swift Trigger 172767 is not a GRB
  7. GRB 051215: Swift detection of a possible burst
  8. GRB 051215: A short GRB in a cluster?
  9. GRB 051213: Swift-BAT refined analysis
  10. GRB051211B: XRT refined analysis
  11. GRB 051213: Swift-BAT detection of a burst
  12. GRB 051211A: Swift/UVOT upper limits
  13. GRB 051211B: Swift/UVOT upper limits - correction
  14. GRB 051211B: Swift/UVOT upper limits
  15. GRB 051211B: Swift XRT confirmation of the afterglow
  16. GRB051211B: Liverpool Telescope observation
  17. GRB 051211B: Swift XRT Observations
  18. GRB 051210: Swift/UVOT upper limits
  19. GRB 051211: Swift XRT upper limit
  20. GRB 051210: SALT detection limit
  21. GRB 051210: BAT further refined analysis of the short burst
  22. GRB 051210: Swift XRT refined analysis
  23. GRB 051210: Swift-BAT refined analysis of a short burst
  24. GRB051210: Swift UVOT Observation
  25. GRB 051210: Swift detection of a burst
  26. IPN observations of SGR1806-20
  27. Swift XRT positions
  28. An extraordinary long burst on December 3 from SGR1806-20
  29. Swift UVOT Calibration Documentation
  30. Swift-BAT trigger 165579 is not a GRB
  31. GRB 051127: Swift-BAT detection of a possible burst
  32. GRB051117B: Swift XRT refined analysis
  33. GRB051117b: No Swift/UVOT Detection
  34. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  35. GRB 051117A: Swift/UVOT Detection of an Afterglow
  36. GRB051111: Rc optical observations
  37. GRB051008: Suzaku WAM observation of the prompt emission
  38. GRB 051117B: MARGE Optical Limits
  39. GRB 051117B: R and I observations of possible host galaxy
  40. GRB 051117A: Refined analysis of the Swift-BAT burst
  41. GRB 051117B: Refined analysis of the Swift-BAT burst
  42. GRB051117A : XRT refined analysis
  43. GRB 051117B,optical observation
  44. GRB 051117B: Lulin R and I band observation
  45. GRB 051117B: Optical observations
  46. GRB 051117B: ROTSE-III Optical Limits
  47. GRB051117B: Swift XRT position
  48. GRB 051117B: Swift detection of a burst
  49. GRB 051117: Swift detection of a bright burst
  50. GRB051114: results of the Swift-XRT observation
  51. GRB 051114: Swift-BAT refined analysis
  52. GRB050925: analysis of the XMM-Newton observation
  53. GRB 051114: Swift-BAT detection of a short burst
  54. GRB 051113: Swift-BAT refined analysis
  55. GRB 051113: Swift-BAT detection of a burst
  56. GRB 051111: AEOS optical observations
  57. GRB 051109A Milagro GeV/TeV Observations
  58. GRB/SGR 050925: XMM-Newton ToO observation
  59. GRB051111: Swift/UVOT Observations
  60. GRB051111: XRT preliminary analysis
  61. GRB 051111: Swift-BAT refined analysis
  62. GRB 051109A Optical Observations
  63. GRB051111a: SARA Observations
  64. GRB 051111A: KAIT optical observations
  65. GRB051111: Super-LOTIS Early Detection
  66. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  67. Faulkes Telescope R-band detection of GRB051111
  68. GRB051111: Swift-BAT detection of a bright burst
  69. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  70. Early RAPTOR measurements of GRB 051109a - the movie.
  71. Konus-Wind observation of GRB 051109A
  72. GRB 051109B: Swift-BAT refined analysis
  73. GRB 051109B: ROTSE-III Optical Limits
  74. GRB 051109A: Swift-UVOT Observations
  75. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  76. GRB051109B: no UVOT source detected
  77. GRB051109B: XRT refined analysis
  78. GRB 051109B : Lulin Optical Observations
  79. GRB051109A: further steepening in the X-ray light curve
  80. GRB051109A: XRT refined analysis
  81. GRB051109B: XRT position
  82. GRB 051109B: Super-LOTIS Observations
  83. GRB 051109B Kiso optical follow-up observation
  84. GRB 051109B: Swift detection of a burst
  85. GRB051109: Early Super-LOTIS Detection
  86. GRB 051109: Swift-BAT refined analysis
  87. GRB 051109a: MDM Observations
  88. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  89. GRB051109: Swift detection of a burst
  90. GRB 051109a: IR Detections
  91. GRB 051109: ROTSE-III Detection of Possible Counterpart
  92. GRB051105B: Swift/XRT upper limit
  93. GRB051105B: Swift/UVOT upper limit
  94. GRB051028: Swift-XRT refined analysis
  95. GRB 051105a: MDM Observations
  96. GRB051105A: Swift/UVOT Observations
  97. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  98. XRT observations of GRB 051105A
  99. GRB 051105: Swift-BAT improved refined analysis
  100. GRB 051105: Swift-BAT refined analysis

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