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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').

18347 results found.

  1. GRB051028: Swift/UVOT upper limits
  2. GRB051028: Swift XRT Position
  3. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  4. GRB051022: Swift XRT measurement of jet break
  5. GRB051021B: Swift/UVOT Upper limits
  6. GRB 051022: XRT Refined Spectral and Temporal Analysis
  7. GRB051012: Swift-XRT analysis
  8. GRB051021B: Swift XRT refined analysis
  9. GRB 051022: WSRT Radio Detection
  10. GRB 051022: Swift/UVOT Upper Limits
  11. GRB051021A: Swift XRT refined analysis
  12. GRB051022: Optical Observations
  13. GRB 051022, J & K-band observation
  14. GRB051022: Swift XRT Position
  15. GRB051021: Swift/UVOT Upper Limits
  16. GRB 051021B: Refined analysis of the Swift-BAT burst
  17. GRB051021B: Swift XRT Position
  18. GRB 051021B: Swift detection of a burst
  19. GRB051021: Swift XRT analysis
  20. GRB051021.63
  21. Swift-BAT trigger 160640 is not a real GRB
  22. Swift-BAT trigger 160619 is not a GRB
  23. Swift-BAT triggered on a posible CR Shower or possible GRB
  24. GRB 051016A: Swift/UVOT upper limits
  25. GRB 051016B: refined analysis of the Swift/XRT data
  26. GRB 051016B: Swift/UVOT detection
  27. GRB 051016B : Optical follow-up at Lulin
  28. GRB 051016B: Refined analysis of the Swift-BAT burst
  29. GRB 051016B: Swift detection of a soft burst
  30. GRB 051016: Swift-BAT refined analysis
  31. GRB051016 XMM-Newton observation
  32. GRB051016: Swift XRT refined analysis.
  33. GRB051016: Swift detection of a burst
  34. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  35. GRB 051012: Swift-BAT detection of burst yesterday
  36. Swift trigger 159578 is not a burst
  37. Swift-BAT Trigger 159578 is a possible burst
  38. GRB050805A: Rc optical observations
  39. GRB 051006: Swift/UVOT Upper Limits
  40. GRB 051008 - a low redshift low-luminosity burst?
  41. GRB051008: Swift XRT refined analysis
  42. GRB051008 - Swift UVOT upper limits
  43. Konus-Wind observation of GRB 051008
  44. GRB051008: Final refined analysis of the Swift-BAT burst
  45. GRB 051008: R-band upper limit
  46. GRB051008: Refined analysis of the Swift-BAT burst
  47. GRB 051008: Swift XRT position
  48. GRB 051008: early Swift XRT analysis
  49. GRB 051008: Swift UVOT Candidate
  50. GRB051008: Swift-BAT detection of a bright burst
  51. GRB 051006: XRT refined analysis
  52. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  53. GRB 051006: optical observations at Sierra Nevada
  54. GRB051006: Refined analysis of the Swift-BAT burst
  55. GRB 051006: XRT position
  56. GRB051006: Swift detection of a burst
  57. Swift-BAT triggers 158261 and 158262 Retraction
  58. GRB051001: Swift UVOT Upper Limits
  59. GRB 050925: Second Epoch WSRT Radio Observations
  60. GRB 051001: Swift XRT refined analysis
  61. GRB 051001, optical observations at Mt. John
  62. GRB 051001: I-band limit
  63. GRB 051001: Swift-BAT refined analysis
  64. GRB 051001: Swift Detection of a Burst
  65. GRB 051001: ROTSE-III Optical Limits
  66. GRB050922B: optical limit
  67. GRB050925: Swift/XRT limits
  68. GRB/SGR 050925: IR Observations
  69. GRB050922C - Swift UVOT preliminary analysis
  70. GRB 050925: WSRT Radio Observations
  71. GRB050925: Swift UVOT upper limits
  72. Refined analysis of the Swift-BAT soft short burst
  73. GRB050925: Faulkes Telescope North R-band limit
  74. GRB050925: Swift-BAT detection of a short burst
  75. GRB 050922B: Correction to BAT refined analysis, longer burst
  76. GRB050922B: refined XRT analysis
  77. Konus-Wind observation of GRB 050922C
  78. GRB050922B: Swift UVOT early upper limits.
  79. GRB 050922B: optical limit
  80. GRB 050922C: Swift XRT refined analysis
  81. HETE Fregate observations of GRB 050922C
  82. GRB 050922C: Swift-BAT refined analysis
  83. GRB 050922B: Swift-BAT refined analysis
  84. GRB050922C: optical observations
  85. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  86. GRB 050922C: optical obserations
  87. GRB 050922C: NOT optical observations
  88. GRB 050922A: Analysis of Swift/XRT TOO observation
  89. GRB 050922C: Swift detection of a bright burst
  90. GRB 050922C: ROTSE-IIId Refined Analysis
  91. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  92. GRB 050922B: ROTSE-III Optical Limits
  93. GRB 050922B,optical observation
  94. GRB050922B: Swift-BAT detection of a weak long burst
  95. GRB050918: Possible Swift/XRT detected afterglow
  96. GRB050820B: analysis of the XMM-Newton observation
  97. GRB050916: Swift/UVOT Upper Limits
  98. GRB 050916: Swift-BAT refined analysis
  99. Swift-BAT trigger 155764 is not a GRB
  100. Swift-BAT trigger 155764 is probably not a GRB

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