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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"

32489 results found.

  1. GRB 050709: PROMPT Rc Observations
  2. GRB050713b: Maidanak optical observations
  3. GRB 050724: Secure Host Redshift from Keck
  4. GRB 050724: WHT optical observations
  5. GRB050726: Swift UVOT observations
  6. GRB 050724: Chandra Observations of the X-ray Afterglow
  7. GRB050724: Refined Radio Position
  8. GRB050713: analysis of the XMM-Newton observation
  9. GRB 050724, SMARTS optical/IR afterglow observations
  10. GRB 050726, SMARTS optical/IR observations
  11. Swift-BAT trigger 147918 is not a real GRB
  12. GRB050724: VLT observations of the variable source
  13. GRB050709: Second Epoch Chandra Observation
  14. GRB 050726: PROMPT Rc Observations
  15. GRB050709: Second Epoch Chandra Observation
  16. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  17. GRB050724: Further Radio Observations
  18. GRB 050726: early Swift XRT analysis results
  19. GRB050726: Swift-BAT detection of a weak burst
  20. GRB 050724: Optical Variability in Nearby Galaxy
  21. GRB 050724: J-band observations
  22. GRB 050724: GMOS Imaging and Spectroscopy
  23. GRB 050724: SWIFT XRT refined position
  24. RXTE ASM Detection of GRB050724
  25. GRB050724: Radio Observation
  26. GRB 050724: spectroscopy of object in the XRT error circle
  27. GRB 050724: Optical limit
  28. GRB 050724: optical and near-IR observations
  29. GRB 050724: Optical imaging/astrometry
  30. GRB 050724: RTT150 optical observations
  31. GRB 050724: Swift/UVOT Upper Limit
  32. GRB 050724: early Swift XRT analysis results
  33. GRB 050724 : Lulin early R-band monitoring observations
  34. GRB050724: Refined analysis of the Swift-BAT possible short burst
  35. GRB 050724: possible host galaxy in DSS
  36. Swift-BAT trigger 147325 is not due to a real GRB
  37. GRB050723: XRT distributed coordinates are not related to the burst
  38. GRB 050721: early afterglow light curve
  39. GRB 050721A: Swift-BAT refined analysis
  40. Correction to GCN Circ 3474 on GRB050525A
  41. GRB 050721A: Early Swift XRT analysis results
  42. GRB050721A: optical decay
  43. GRB 050721: optical afterglow confirmed
  44. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  45. GRB 050721a: Optical Observations
  46. GRB 050709: Refined Spectral and Temporal Properties
  47. GRB 050717: PROMPT RcIc Observations
  48. GRB050714b: Radio Observation
  49. GRB050712: Radio Observations
  50. GRB 050714a: Refined XRT analysis and afterglow confirmation
  51. GRB050713a: Radio Observation
  52. Swift-BAT trigger 146731 is not a real GRB
  53. GRB 050712, Tautenburg optical afterglow observations
  54. GRB 050714B: VLT R-band observations
  55. GRB 050717: Additional LCO observations
  56. GRB050717
  57. GRB 050716; J-band observations
  58. Konus-Wind observation of GRB 050717
  59. GRB 050717: LCO near-IR observations
  60. Swift/UVOT Observations of GRB 050717
  61. GRB 050717: Swift-BAT refined analysis
  62. GRB 050717: Refined XRT analysis.
  63. GRB050712: optical limits
  64. GRB050717: Swift XRT position
  65. GRB 050716 - UKIRT identification of candidate afterglow
  66. Swift UVOT Observations of GRB 050716
  67. GRB 050716: Refined XRT analysis.
  68. GRB050716: Refined analysis of the Swift-BAT burst
  69. GRB 050716: Lulin B and R band optical observations
  70. GRB050716, optical observation
  71. GRB 050716: Optical Observations
  72. GRB050716: Faulkes North Telescope observation
  73. GRB050716: Correction to sign in XRT coordinate
  74. GRB050715: Refined analysis of the Swift-BAT burst
  75. Swift UVOT Observations of GRB 050714B
  76. Konus-Wind observation of GRB 050713A
  77. GRB 050714B: refined XRT analysis
  78. GRB 050713b: RTT150 optical observations
  79. GRB 050714B: candidate afterglow does not fade
  80. GRB050714B: Refined analysis of the Swift-BAT burst
  81. GRB 050714B: optical afterglow
  82. GRB 050709: optical afterglow candidate
  83. GRB 050714, R-band candidate
  84. GRB 050714: Swift XRT afterglow position
  85. GRB 050714, optical observations
  86. GRB 050714A: ROTSE-III Optical Limits
  87. GRB 050713A: XRT refined analysis
  88. GRB 050709: Spectroscopy
  89. GRB 050713A: RAPTOR detection of early optical emission
  90. GRB050713B :Swift/UVOT observations
  91. GRB050713b: XRT refined analysis
  92. GRB050712: TNG R-band observations
  93. GRB 050713B: Swift-BAT Refined Analysis
  94. Swift-BAT Trigger 145729 is not a GRB
  95. GRB 050713A: Swift/UVOT observation
  96. GRB 050713A : Swift-BAT Refined Analysis
  97. GRB050712: Swift UVOT Observation of Afterglow Emission
  98. GRB 050713A XMM-Newton observation
  99. GRB 050713b : Lulin R-band observations
  100. GRB050713B: Faulkes North Telescope observation

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