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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"

45459 results found.

  1. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  2. GRB 050730, SMARTS optical/IR afterglow observations
  3. GRB 050730 : Planned XMM-Newton observation
  4. GRB050730: Liverpool Telescope optical observations
  5. GRB 050730, optical candidate
  6. GRB050730: Swift-BAT detection of a weak burst
  7. GRB 050713A: Swift XRT extended light curve
  8. GRB 050709: PROMPT Rc Observations
  9. GRB050713b: Maidanak optical observations
  10. GRB 050724: Secure Host Redshift from Keck
  11. GRB 050724: WHT optical observations
  12. GRB050726: Swift UVOT observations
  13. GRB 050724: Chandra Observations of the X-ray Afterglow
  14. GRB050724: Refined Radio Position
  15. GRB050713: analysis of the XMM-Newton observation
  16. GRB 050724, SMARTS optical/IR afterglow observations
  17. GRB 050726, SMARTS optical/IR observations
  18. Swift-BAT trigger 147918 is not a real GRB
  19. GRB 050727: RTT150 optical observations
  20. GRB050724: VLT observations of the variable source
  21. GRB050727: KAIT optical limit
  22. GRB050709: Second Epoch Chandra Observation
  23. GRB 050726: PROMPT Rc Observations
  24. GRB050709: Second Epoch Chandra Observation
  25. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  26. GRB050724: Further Radio Observations
  27. GRB 050726: early Swift XRT analysis results
  28. GRB050726: Swift-BAT detection of a weak burst
  29. GRB 050724: Optical Variability in Nearby Galaxy
  30. GRB 050724: J-band observations
  31. GRB 050724: GMOS Imaging and Spectroscopy
  32. GRB 050724: SWIFT XRT refined position
  33. RXTE ASM Detection of GRB050724
  34. GRB050724: Radio Observation
  35. GRB 050724: spectroscopy of object in the XRT error circle
  36. GRB 050724: Optical limit
  37. GRB 050724: optical and near-IR observations
  38. GRB 050724: Optical imaging/astrometry
  39. GRB 050724: RTT150 optical observations
  40. GRB 050724: Swift/UVOT Upper Limit
  41. GRB 050724: early Swift XRT analysis results
  42. GRB 050724 : Lulin early R-band monitoring observations
  43. GRB050724: Refined analysis of the Swift-BAT possible short burst
  44. GRB 050724: possible host galaxy in DSS
  45. GRB050724: a short-burst detected by Swift
  46. Swift-BAT trigger 147325 is not due to a real GRB
  47. GRB050723: XRT distributed coordinates are not related to the burst
  48. GRB 050721: early afterglow light curve
  49. GRB 050721A: Swift-BAT refined analysis
  50. Correction to GCN Circ 3474 on GRB050525A
  51. GRB 050721A: Early Swift XRT analysis results
  52. GRB050721A: optical decay
  53. GRB 050721: optical afterglow confirmed
  54. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  55. GRB 050721a: Optical Observations
  56. GRB050721A: Swift-BAT detection of a weak burst
  57. GRB 050709: Refined Spectral and Temporal Properties
  58. GRB 050717: PROMPT RcIc Observations
  59. GRB050714b: Radio Observation
  60. GRB050712: Radio Observations
  61. GRB 050714a: Refined XRT analysis and afterglow confirmation
  62. GRB050713a: Radio Observation
  63. Swift-BAT trigger 146731 is not a real GRB
  64. GRB 050712, Tautenburg optical afterglow observations
  65. Swift-BAT detection of a possible GRB
  66. GRB 050714B: VLT R-band observations
  67. GRB 050717: Additional LCO observations
  68. GRB050717
  69. GRB 050716; J-band observations
  70. Konus-Wind observation of GRB 050717
  71. GRB 050717: LCO near-IR observations
  72. Swift/UVOT Observations of GRB 050717
  73. GRB 050717: Swift-BAT refined analysis
  74. GRB 050717: Refined XRT analysis.
  75. GRB050712: optical limits
  76. GRB050717: Swift XRT position
  77. Swift detection of GRB 050717
  78. GRB 050716 - UKIRT identification of candidate afterglow
  79. Swift UVOT Observations of GRB 050716
  80. GRB 050716: Refined XRT analysis.
  81. GRB050716: Refined analysis of the Swift-BAT burst
  82. GRB 050716: Lulin B and R band optical observations
  83. GRB050716, optical observation
  84. GRB 050716: Optical Observations
  85. GRB050716: Faulkes North Telescope observation
  86. GRB050716: Correction to sign in XRT coordinate
  87. Swift/BAT detection of GRB 050716
  88. GRB050715: Refined analysis of the Swift-BAT burst
  89. GRB 050715: Swift-BAT detection
  90. Swift UVOT Observations of GRB 050714B
  91. Konus-Wind observation of GRB 050713A
  92. GRB 050714B: refined XRT analysis
  93. GRB 050713b: RTT150 optical observations
  94. GRB 050714B: candidate afterglow does not fade
  95. GRB050714B: Refined analysis of the Swift-BAT burst
  96. GRB 050714B: optical afterglow
  97. Swift detection of a long transient (GRB 050714B?)
  98. GRB 050709: optical afterglow candidate
  99. GRB 050714, R-band candidate
  100. GRB 050714: Swift XRT afterglow position

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