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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').
Advanced Search

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"

18396 results found.

  1. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  2. GRB050805a: MASTER optical candidat
  3. Swift-BAT trigger 149118 is probably not a GRB
  4. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  5. GRB 050803: Swift-BAT refined analysis
  6. GRB050803: MASTER further analys
  7. GRB 050803: early Swift XRT analysis results
  8. GRB 050803: TAROT optical limits
  9. GRB050803: MASTER optical observations
  10. GRB050803: Swift-BAT detection of a very long burst
  11. GCN GRB observation 050713A
  12. GRB 050802: Swift/UVOT optical and UV detections
  13. GRB050802 radio non-detection
  14. GRB 050730: OHP optical observations
  15. GRB 050802: early Swift XRT analysis results
  16. GRB 050802: Swift/UVOT observations
  17. GRB 050802: Swift-BAT refined analysis
  18. GRB 050802: XRT position
  19. GRB 050802: Swift Gamma-ray Burst
  20. GRB050801: Swift/UVOT Optical and UV detections
  21. GCN 050801: early Swift XRT analysis results
  22. GRB 050801: Swift-BAT refined analysis
  23. GRB 050801, afterglow observations
  24. GRB 050730, corrected photometry and break?
  25. GRB 050801: ROTSE-III Early Afterglow Break
  26. GRB050801: Swift-BAT detection of a burst
  27. GRB050801: GCN XRT position is incorrect
  28. GRB 050801: ROTSE-III Detection of Possible Counterpart
  29. GRB 050730: XRT refined analysis
  30. GRB 050730: early TAROT optical observations
  31. Swift/UVOT photometry of GRB050730
  32. GRB050730: Refined BAT analysis of the Swift-BAT burst
  33. GRB 050730: Swift XRT afterglow observations
  34. GRB 050730 XMM-Newton observation
  35. GRB050730, afterglow observations
  36. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  37. GRB050730: Liverpool Telescope optical observations
  38. GRB 050730, optical candidate
  39. GRB050730: Swift-BAT detection of a weak burst
  40. GRB 050713A: Swift XRT extended light curve
  41. GRB050726: Swift UVOT observations
  42. GRB 050724: Chandra Observations of the X-ray Afterglow
  43. GRB050713: analysis of the XMM-Newton observation
  44. Swift-BAT trigger 147918 is not a real GRB
  45. GRB 050727: RTT150 optical observations
  46. GRB050727: KAIT optical limit
  47. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  48. GRB 050726: early Swift XRT analysis results
  49. GRB050726: Swift-BAT detection of a weak burst
  50. GRB 050724: SWIFT XRT refined position
  51. GRB 050724: optical and near-IR observations
  52. GRB 050724: Swift/UVOT Upper Limit
  53. GRB 050724: early Swift XRT analysis results
  54. GRB050724: Refined analysis of the Swift-BAT possible short burst
  55. GRB050724: a short-burst detected by Swift
  56. Swift-BAT trigger 147325 is not due to a real GRB
  57. GRB050723: XRT distributed coordinates are not related to the burst
  58. GRB 050721A: Swift-BAT refined analysis
  59. GRB 050721A: Early Swift XRT analysis results
  60. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  61. GRB 050721a: Optical Observations
  62. GRB050721A: Swift-BAT detection of a weak burst
  63. GRB 050714a: Refined XRT analysis and afterglow confirmation
  64. Swift-BAT trigger 146731 is not a real GRB
  65. Swift-BAT detection of a possible GRB
  66. GRB050717
  67. Konus-Wind observation of GRB 050717
  68. Swift/UVOT Observations of GRB 050717
  69. GRB 050717: Swift-BAT refined analysis
  70. GRB 050717: Refined XRT analysis.
  71. GRB050712: optical limits
  72. GRB050717: Swift XRT position
  73. Swift detection of GRB 050717
  74. GRB 050716 - UKIRT identification of candidate afterglow
  75. Swift UVOT Observations of GRB 050716
  76. GRB 050716: Refined XRT analysis.
  77. GRB050716: Refined analysis of the Swift-BAT burst
  78. GRB050716, optical observation
  79. GRB050716: Faulkes North Telescope observation
  80. GRB050716: Correction to sign in XRT coordinate
  81. Swift/BAT detection of GRB 050716
  82. GRB050715: Refined analysis of the Swift-BAT burst
  83. GRB 050715: Swift-BAT detection
  84. Swift UVOT Observations of GRB 050714B
  85. Konus-Wind observation of GRB 050713A
  86. GRB 050714B: refined XRT analysis
  87. GRB050714B: Refined analysis of the Swift-BAT burst
  88. Swift detection of a long transient (GRB 050714B?)
  89. GRB 050714: Swift XRT afterglow position
  90. GRB 050713A: XRT refined analysis
  91. GRB 050713A: RAPTOR detection of early optical emission
  92. GRB050713B :Swift/UVOT observations
  93. GRB050713b: XRT refined analysis
  94. GRB 050713B: Swift-BAT Refined Analysis
  95. Swift-BAT Trigger 145729 is not a GRB
  96. GRB 050713A: Swift/UVOT observation
  97. GRB 050713A : Swift-BAT Refined Analysis
  98. GRB050712: Swift UVOT Observation of Afterglow Emission
  99. GRB 050713A XMM-Newton observation
  100. GRB050713B: Faulkes North Telescope observation

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