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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').

17828 results found.

  1. GRB 051210: SALT detection limit
  2. GRB 051210: BAT further refined analysis of the short burst
  3. GRB 051210: Swift XRT refined analysis
  4. GRB 051210: Swift-BAT refined analysis of a short burst
  5. GRB051210: Swift UVOT Observation
  6. GRB 051210: Swift detection of a burst
  7. IPN observations of SGR1806-20
  8. Swift XRT positions
  9. An extraordinary long burst on December 3 from SGR1806-20
  10. Swift UVOT Calibration Documentation
  11. Swift-BAT trigger 165579 is not a GRB
  12. GRB 051127: Swift-BAT detection of a possible burst
  13. GRB051117B: Swift XRT refined analysis
  14. GRB051117b: No Swift/UVOT Detection
  15. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  16. GRB 051117A: Swift/UVOT Detection of an Afterglow
  17. GRB051111: Rc optical observations
  18. GRB051008: Suzaku WAM observation of the prompt emission
  19. GRB 051117B: MARGE Optical Limits
  20. GRB 051117B: R and I observations of possible host galaxy
  21. GRB 051117A: Refined analysis of the Swift-BAT burst
  22. GRB 051117B: Refined analysis of the Swift-BAT burst
  23. GRB051117A : XRT refined analysis
  24. GRB 051117B,optical observation
  25. GRB 051117B: Lulin R and I band observation
  26. GRB 051117B: Optical observations
  27. GRB 051117B: ROTSE-III Optical Limits
  28. GRB051117B: Swift XRT position
  29. GRB 051117B: Swift detection of a burst
  30. GRB 051117: Swift detection of a bright burst
  31. GRB051114: results of the Swift-XRT observation
  32. GRB 051114: Swift-BAT refined analysis
  33. GRB050925: analysis of the XMM-Newton observation
  34. GRB 051114: Swift-BAT detection of a short burst
  35. GRB 051113: Swift-BAT refined analysis
  36. GRB 051113: Swift-BAT detection of a burst
  37. GRB 051111: AEOS optical observations
  38. GRB 051109A Milagro GeV/TeV Observations
  39. GRB/SGR 050925: XMM-Newton ToO observation
  40. GRB051111: Swift/UVOT Observations
  41. GRB051111: XRT preliminary analysis
  42. GRB 051111: Swift-BAT refined analysis
  43. GRB 051109A Optical Observations
  44. GRB051111a: SARA Observations
  45. GRB 051111A: KAIT optical observations
  46. GRB051111: Super-LOTIS Early Detection
  47. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  48. Faulkes Telescope R-band detection of GRB051111
  49. GRB051111: Swift-BAT detection of a bright burst
  50. GRB 051111A: ROTSE-III Detection of Possible Counterpart
  51. Early RAPTOR measurements of GRB 051109a - the movie.
  52. Konus-Wind observation of GRB 051109A
  53. GRB 051109B: Swift-BAT refined analysis
  54. GRB 051109B: ROTSE-III Optical Limits
  55. GRB 051109A: Swift-UVOT Observations
  56. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  57. GRB051109B: no UVOT source detected
  58. GRB051109B: XRT refined analysis
  59. GRB 051109B : Lulin Optical Observations
  60. GRB051109A: further steepening in the X-ray light curve
  61. GRB051109A: XRT refined analysis
  62. GRB051109B: XRT position
  63. GRB 051109B: Super-LOTIS Observations
  64. GRB 051109B Kiso optical follow-up observation
  65. GRB 051109B: Swift detection of a burst
  66. GRB051109: Early Super-LOTIS Detection
  67. GRB 051109: Swift-BAT refined analysis
  68. GRB 051109a: MDM Observations
  69. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  70. GRB051109: Swift detection of a burst
  71. GRB 051109a: IR Detections
  72. GRB 051109: ROTSE-III Detection of Possible Counterpart
  73. GRB051105B: Swift/XRT upper limit
  74. GRB051105B: Swift/UVOT upper limit
  75. GRB051028: Swift-XRT refined analysis
  76. GRB 051105a: MDM Observations
  77. GRB051105A: Swift/UVOT Observations
  78. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  79. XRT observations of GRB 051105A
  80. GRB 051105: Swift-BAT improved refined analysis
  81. GRB 051105: Swift-BAT refined analysis
  82. GRB 051105: Swift detection of a short burst
  83. GRB051028: Swift/UVOT upper limits
  84. GRB051028: Swift XRT Position
  85. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  86. GRB051022: Swift XRT measurement of jet break
  87. GRB051021B: Swift/UVOT Upper limits
  88. GRB 051022: XRT Refined Spectral and Temporal Analysis
  89. GRB051012: Swift-XRT analysis
  90. GRB051021B: Swift XRT refined analysis
  91. GRB 051022: WSRT Radio Detection
  92. GRB 051022: Swift/UVOT Upper Limits
  93. GRB051021A: Swift XRT refined analysis
  94. GRB051022: Optical Observations
  95. GRB 051022, J & K-band observation
  96. GRB051022: Swift XRT Position
  97. GRB051021: Swift/UVOT Upper Limits
  98. GRB 051021B: Refined analysis of the Swift-BAT burst
  99. GRB051021B: Swift XRT Position
  100. GRB 051021B: Swift detection of a burst

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