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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"

36079 results found.

  1. GRB 050726: PROMPT Rc Observations
  2. GRB050709: Second Epoch Chandra Observation
  3. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  4. GRB 050726: early Swift XRT analysis results
  5. GRB 050724: Optical Variability in Nearby Galaxy
  6. GRB 050724: J-band observations
  7. GRB 050724: GMOS Imaging and Spectroscopy
  8. GRB 050724: SWIFT XRT refined position
  9. GRB 050724: spectroscopy of object in the XRT error circle
  10. GRB 050724: Optical limit
  11. GRB 050724: optical and near-IR observations
  12. GRB 050724: Optical imaging/astrometry
  13. GRB 050724: RTT150 optical observations
  14. GRB 050724: Swift/UVOT Upper Limit
  15. GRB 050724: early Swift XRT analysis results
  16. GRB 050724 : Lulin early R-band monitoring observations
  17. GRB050724: Refined analysis of the Swift-BAT possible short burst
  18. GRB 050724: possible host galaxy in DSS
  19. Swift-BAT trigger 147325 is not due to a real GRB
  20. GRB050723: XRT distributed coordinates are not related to the burst
  21. GRB 050721: early afterglow light curve
  22. GRB 050721A: Swift-BAT refined analysis
  23. Correction to GCN Circ 3474 on GRB050525A
  24. GRB 050721A: Early Swift XRT analysis results
  25. GRB050721A: optical decay
  26. GRB 050721: optical afterglow confirmed
  27. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  28. GRB 050721a: Optical Observations
  29. GRB 050709: Refined Spectral and Temporal Properties
  30. GRB 050717: PROMPT RcIc Observations
  31. GRB 050714a: Refined XRT analysis and afterglow confirmation
  32. Swift-BAT trigger 146731 is not a real GRB
  33. GRB 050712, Tautenburg optical afterglow observations
  34. Swift-BAT detection of a possible GRB
  35. GRB 050714B: VLT R-band observations
  36. GRB 050717: Additional LCO observations
  37. GRB050717
  38. GRB 050716; J-band observations
  39. Konus-Wind observation of GRB 050717
  40. GRB 050717: LCO near-IR observations
  41. Swift/UVOT Observations of GRB 050717
  42. GRB 050717: Swift-BAT refined analysis
  43. GRB 050717: Refined XRT analysis.
  44. GRB050712: optical limits
  45. Swift detection of GRB 050717
  46. GRB 050716 - UKIRT identification of candidate afterglow
  47. Swift UVOT Observations of GRB 050716
  48. GRB 050716: Refined XRT analysis.
  49. GRB 050716: Lulin B and R band optical observations
  50. GRB050716, optical observation
  51. GRB 050716: Optical Observations
  52. GRB050716: Faulkes North Telescope observation
  53. Swift/BAT detection of GRB 050716
  54. GRB 050715: Swift-BAT detection
  55. Swift UVOT Observations of GRB 050714B
  56. Konus-Wind observation of GRB 050713A
  57. GRB 050714B: refined XRT analysis
  58. GRB 050713b: RTT150 optical observations
  59. GRB 050714B: candidate afterglow does not fade
  60. GRB050714B: Refined analysis of the Swift-BAT burst
  61. GRB 050714B: optical afterglow
  62. Swift detection of a long transient (GRB 050714B?)
  63. GRB 050709: optical afterglow candidate
  64. GRB 050714, R-band candidate
  65. GRB 050714: Swift XRT afterglow position
  66. GRB 050714, optical observations
  67. GRB 050714A: ROTSE-III Optical Limits
  68. GRB 050714 - A long GRB detected with INTEGRAL
  69. GRB 050713A: XRT refined analysis
  70. GRB 050709: Spectroscopy
  71. GRB 050713A: RAPTOR detection of early optical emission
  72. GRB050713B :Swift/UVOT observations
  73. GRB050712: TNG R-band observations
  74. GRB 050713B: Swift-BAT Refined Analysis
  75. Swift-BAT Trigger 145729 is not a GRB
  76. GRB 050713A: Swift/UVOT observation
  77. GRB 050713A : Swift-BAT Refined Analysis
  78. GRB 050713A : Lulin R-band observation
  79. GRB 050713A XMM-Newton observation
  80. GRB 050713b : Lulin R-band observations
  81. GRB050713B: Faulkes North Telescope observation
  82. RBO RI observations of GRB 050713A
  83. GRB 050713B
  84. GRB050709 : Chandra source optical counterpart
  85. GRB050713: Liverpool Telescope prompt observations
  86. GRB 050712, optical observations
  87. GRB 050713 : Planned XMM-Newton observation
  88. GRB050709: Candidate X-ray Afterglow from Chandra
  89. GRB 050713, R-band observations at NOT
  90. GRB 050713: ARC NIR Detections and Identification of Fading
  91. GRB050713: possible I-band afterglow
  92. GRB 050713: Swift detection of Bright Burst
  93. GRB 050713A: ROTSE-III Optical Limits
  94. GRB 050709: Swift UVOT and XRT observations
  95. GRB 050712: Swift-BAT Refined Analysis
  96. GRB 050712: Swift XRT afterglow position
  97. GRB 050712: Swift detection of a weak burst
  98. GRB 050709: LCO40 Observations
  99. GRB050709: A Possible Short-Hard GRB Localized by HETE
  100. PROMPT Rc Observations of GRB 050709

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