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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18991 results found.

  1. GRB 051109a: MDM Observations
  2. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  3. GRB051109: Swift detection of a burst
  4. GRB 051109a: IR Detections
  5. GRB 051109: ROTSE-III Detection of Possible Counterpart
  6. GRB051105B: Swift/XRT upper limit
  7. GRB051105B: Swift/UVOT upper limit
  8. GRB051103: MASTER: OT limit and host galaxy candidates
  9. GRB051028: Swift-XRT refined analysis
  10. GRB 051105a: MDM Observations
  11. GRB051105A: Swift/UVOT Observations
  12. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  13. XRT observations of GRB 051105A
  14. GRB 051105: Swift-BAT improved refined analysis
  15. GRB 051105: Swift-BAT refined analysis
  16. GRB 051105: Swift detection of a short burst
  17. GRB051028: Swift/UVOT upper limits
  18. GRB051028: Swift XRT Position
  19. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  20. GRB051022: Swift XRT measurement of jet break
  21. SGR 1806-20: continued moderate activity seen with INTEGRAL
  22. GRB051021B: Swift/UVOT Upper limits
  23. GRB 051022: XRT Refined Spectral and Temporal Analysis
  24. GRB051012: Swift-XRT analysis
  25. GRB051021B: Swift XRT refined analysis
  26. GRB 051022: WSRT Radio Detection
  27. GRB 051022: Swift/UVOT Upper Limits
  28. GRB051021A: Swift XRT refined analysis
  29. GRB051022: Optical Observations
  30. GRB 051022, J & K-band observation
  31. GRB051022: Swift XRT Position
  32. GRB051021: Swift/UVOT Upper Limits
  33. GRB 051021B: Refined analysis of the Swift-BAT burst
  34. GRB051021B: Swift XRT Position
  35. GRB 051021B: Swift detection of a burst
  36. GRB051021: Swift XRT analysis
  37. GRB051021.63
  38. Swift-BAT trigger 160640 is not a real GRB
  39. Swift-BAT trigger 160619 is not a GRB
  40. Swift-BAT triggered on a posible CR Shower or possible GRB
  41. GRB 051016A: Swift/UVOT upper limits
  42. GRB 051016B: refined analysis of the Swift/XRT data
  43. GRB 051016B: Swift/UVOT detection
  44. GRB 051016B : Optical follow-up at Lulin
  45. GRB 051016B: Refined analysis of the Swift-BAT burst
  46. GRB 051016B: Swift detection of a soft burst
  47. GRB 051016: Swift-BAT refined analysis
  48. GRB051016 XMM-Newton observation
  49. GRB051016: Swift XRT refined analysis.
  50. GRB051016: Swift detection of a burst
  51. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  52. GRB 051012: Swift-BAT detection of burst yesterday
  53. Swift trigger 159578 is not a burst
  54. Swift-BAT Trigger 159578 is a possible burst
  55. GRB050805A: Rc optical observations
  56. GRB 051006: Swift/UVOT Upper Limits
  57. GRB 051008 - a low redshift low-luminosity burst?
  58. GRB051008: Swift XRT refined analysis
  59. GRB051008 - Swift UVOT upper limits
  60. Konus-Wind observation of GRB 051008
  61. GRB051008: Final refined analysis of the Swift-BAT burst
  62. GRB 051008: R-band upper limit
  63. GRB051008: Refined analysis of the Swift-BAT burst
  64. GRB 051008: Swift XRT position
  65. GRB 051008: early Swift XRT analysis
  66. GRB 051008: Swift UVOT Candidate
  67. GRB051008: Swift-BAT detection of a bright burst
  68. GRB 051006: XRT refined analysis
  69. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  70. GRB 051006: optical observations at Sierra Nevada
  71. GRB051006: Refined analysis of the Swift-BAT burst
  72. GRB 051006: XRT position
  73. GRB051006: Swift detection of a burst
  74. Swift-BAT triggers 158261 and 158262 Retraction
  75. GRB051001: Swift UVOT Upper Limits
  76. GRB 050925: Second Epoch WSRT Radio Observations
  77. GRB 051001: Swift XRT refined analysis
  78. GRB 051001, optical observations at Mt. John
  79. GRB 051001: I-band limit
  80. GRB 051001: Swift-BAT refined analysis
  81. GRB 051001: Swift Detection of a Burst
  82. GRB 051001: ROTSE-III Optical Limits
  83. GRB050922B: optical limit
  84. GRB050925: Swift/XRT limits
  85. GRB/SGR 050925: IR Observations
  86. GRB050922C - Swift UVOT preliminary analysis
  87. GRB 050925: WSRT Radio Observations
  88. GRB050925: Swift UVOT upper limits
  89. Refined analysis of the Swift-BAT soft short burst
  90. GRB050925: Faulkes Telescope North R-band limit
  91. GRB050925: Swift-BAT detection of a short burst
  92. GRB 050922B: Correction to BAT refined analysis, longer burst
  93. GRB050922B: refined XRT analysis
  94. Konus-Wind observation of GRB 050922C
  95. GRB050922B: Swift UVOT early upper limits.
  96. GRB 050922B: optical limit
  97. GRB 050922C: Swift XRT refined analysis
  98. HETE Fregate observations of GRB 050922C
  99. GRB 050922C: Swift-BAT refined analysis
  100. GRB 050922B: Swift-BAT refined analysis

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