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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"

28057 results found.

  1. GRB050709: Second Epoch Chandra Observation
  2. GRB050726: Swift-BAT detection of a weak burst
  3. GRB 050724: Optical Variability in Nearby Galaxy
  4. GRB 050724: J-band observations
  5. GRB 050724: GMOS Imaging and Spectroscopy
  6. GRB050724: Radio Observation
  7. GRB 050724: Optical imaging/astrometry
  8. GRB 050724: Swift/UVOT Upper Limit
  9. GRB050724: Refined analysis of the Swift-BAT possible short burst
  10. GRB 050724: possible host galaxy in DSS
  11. GRB 050721A: Swift-BAT refined analysis
  12. GRB 050721A: Early Swift XRT analysis results
  13. GRB050721A: optical decay
  14. GRB 050721: optical afterglow confirmed
  15. GRB 050709: Refined Spectral and Temporal Properties
  16. GRB050714b: Radio Observation
  17. GRB050712: Radio Observations
  18. GRB050713a: Radio Observation
  19. GRB 050712, Tautenburg optical afterglow observations
  20. Swift-BAT detection of a possible GRB
  21. GRB 050714B: VLT R-band observations
  22. GRB 050717: Additional LCO observations
  23. GRB 050716; J-band observations
  24. GRB 050717: LCO near-IR observations
  25. Swift/UVOT Observations of GRB 050717
  26. GRB 050717: Swift-BAT refined analysis
  27. GRB050717: Swift XRT position
  28. Swift detection of GRB 050717
  29. Swift UVOT Observations of GRB 050716
  30. GRB 050716: Refined XRT analysis.
  31. GRB050716: Refined analysis of the Swift-BAT burst
  32. GRB 050716: Lulin B and R band optical observations
  33. GRB050716, optical observation
  34. GRB050716: Faulkes North Telescope observation
  35. GRB050715: Refined analysis of the Swift-BAT burst
  36. GRB 050715: Swift-BAT detection
  37. GRB 050713b: RTT150 optical observations
  38. GRB050714B: Refined analysis of the Swift-BAT burst
  39. GRB 050714B: optical afterglow
  40. GRB 050714, R-band candidate
  41. GRB 050714, optical observations
  42. GRB 050713A: XRT refined analysis
  43. GRB 050713A: RAPTOR detection of early optical emission
  44. GRB050713B :Swift/UVOT observations
  45. GRB050713b: XRT refined analysis
  46. GRB050712: TNG R-band observations
  47. GRB 050713B: Swift-BAT Refined Analysis
  48. GRB 050713A: Swift/UVOT observation
  49. GRB 050713A : Swift-BAT Refined Analysis
  50. GRB050712: Swift UVOT Observation of Afterglow Emission
  51. GRB 050713A : Lulin R-band observation
  52. GRB 050713A XMM-Newton observation
  53. GRB 050713b : Lulin R-band observations
  54. GRB050713B: Faulkes North Telescope observation
  55. RBO RI observations of GRB 050713A
  56. GRB 050713B
  57. GRB050709 : Chandra source optical counterpart
  58. GRB050713: Liverpool Telescope prompt observations
  59. GRB 050712, optical observations
  60. GRB050709: Candidate X-ray Afterglow from Chandra
  61. GRB050713: possible I-band afterglow
  62. GRB050712: XRT refined analysis
  63. GRB050709: Radio Observations
  64. GRB 050709: Swift UVOT and XRT observations
  65. GRB 050712: Swift-BAT Refined Analysis
  66. GRB050712: UVOT candidate optical counterpart
  67. GRB 050709: LCO40 Observations
  68. GRB050709, optical observations
  69. PROMPT Rc Observations of GRB 050709
  70. GRB 050525a: PROMPT VRcIc Detections
  71. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  72. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  73. GRB 050626: Swift XRT observations
  74. GRB 050408: ARC 3.5-meter NIR Observations
  75. GRB 050701: Refined XRT analysis
  76. Swift UVOT observations of GRB 050701
  77. GRB050701: Swift-BAT Refined analysis
  78. Swift trigger 143708 is really GRB 050701
  79. GRB 050607, radio observations
  80. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  81. GRB050525a: HST Observations
  82. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  83. XRF 050509c: Optical monitoring
  84. Konus-Wind observation of an intermediate burst from SGR 1806-20
  85. XRF050509c: Radio Detection
  86. GRB 050607 optical decay
  87. GRB050607: refined analysis of prompt REM observations
  88. GRB 050607: PROMPT VRcIc Observations
  89. GRB 050607: Optical decay and spectral slope
  90. GRB050607,optical observation
  91. Optical Afterglow of GRB 050607
  92. GRB050607: Swift Detection of a long GRB
  93. GRB050607: prompt REM observations
  94. Limits on a SN in the field of GRB 050509b
  95. GRB 050603 - XRT data analysis of the first day
  96. GRB050603, submillimetre observations
  97. GRB050603: Radio Detection
  98. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  99. GRB 050603: INTEGRAL shows it is not a short GRB
  100. GRB 050525a, infrared observations

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