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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"

28055 results found.

  1. GRB 050724: Optical Variability in Nearby Galaxy
  2. GRB 050724: J-band observations
  3. GRB 050724: GMOS Imaging and Spectroscopy
  4. GRB050724: Radio Observation
  5. GRB 050724: Optical imaging/astrometry
  6. GRB 050724: Swift/UVOT Upper Limit
  7. GRB050724: Refined analysis of the Swift-BAT possible short burst
  8. GRB 050724: possible host galaxy in DSS
  9. GRB 050721A: Swift-BAT refined analysis
  10. GRB 050721A: Early Swift XRT analysis results
  11. GRB050721A: optical decay
  12. GRB 050721: optical afterglow confirmed
  13. GRB 050709: Refined Spectral and Temporal Properties
  14. GRB050714b: Radio Observation
  15. GRB050712: Radio Observations
  16. GRB050713a: Radio Observation
  17. GRB 050712, Tautenburg optical afterglow observations
  18. Swift-BAT detection of a possible GRB
  19. GRB 050714B: VLT R-band observations
  20. GRB 050717: Additional LCO observations
  21. GRB 050716; J-band observations
  22. GRB 050717: LCO near-IR observations
  23. Swift/UVOT Observations of GRB 050717
  24. GRB 050717: Swift-BAT refined analysis
  25. GRB050717: Swift XRT position
  26. Swift detection of GRB 050717
  27. Swift UVOT Observations of GRB 050716
  28. GRB 050716: Refined XRT analysis.
  29. GRB050716: Refined analysis of the Swift-BAT burst
  30. GRB 050716: Lulin B and R band optical observations
  31. GRB050716, optical observation
  32. GRB050716: Faulkes North Telescope observation
  33. GRB050715: Refined analysis of the Swift-BAT burst
  34. GRB 050715: Swift-BAT detection
  35. GRB 050713b: RTT150 optical observations
  36. GRB050714B: Refined analysis of the Swift-BAT burst
  37. GRB 050714B: optical afterglow
  38. GRB 050714, R-band candidate
  39. GRB 050714, optical observations
  40. GRB 050713A: XRT refined analysis
  41. GRB 050713A: RAPTOR detection of early optical emission
  42. GRB050713B :Swift/UVOT observations
  43. GRB050713b: XRT refined analysis
  44. GRB050712: TNG R-band observations
  45. GRB 050713B: Swift-BAT Refined Analysis
  46. GRB 050713A: Swift/UVOT observation
  47. GRB 050713A : Swift-BAT Refined Analysis
  48. GRB050712: Swift UVOT Observation of Afterglow Emission
  49. GRB 050713A : Lulin R-band observation
  50. GRB 050713A XMM-Newton observation
  51. GRB 050713b : Lulin R-band observations
  52. GRB050713B: Faulkes North Telescope observation
  53. RBO RI observations of GRB 050713A
  54. GRB 050713B
  55. GRB050709 : Chandra source optical counterpart
  56. GRB050713: Liverpool Telescope prompt observations
  57. GRB 050712, optical observations
  58. GRB050709: Candidate X-ray Afterglow from Chandra
  59. GRB050713: possible I-band afterglow
  60. GRB050712: XRT refined analysis
  61. GRB050709: Radio Observations
  62. GRB 050709: Swift UVOT and XRT observations
  63. GRB 050712: Swift-BAT Refined Analysis
  64. GRB050712: UVOT candidate optical counterpart
  65. GRB 050709: LCO40 Observations
  66. GRB050709, optical observations
  67. PROMPT Rc Observations of GRB 050709
  68. GRB 050525a: PROMPT VRcIc Detections
  69. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  70. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  71. GRB 050626: Swift XRT observations
  72. GRB 050408: ARC 3.5-meter NIR Observations
  73. GRB 050701: Refined XRT analysis
  74. Swift UVOT observations of GRB 050701
  75. GRB050701: Swift-BAT Refined analysis
  76. Swift trigger 143708 is really GRB 050701
  77. GRB 050607, radio observations
  78. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  79. GRB050525a: HST Observations
  80. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  81. XRF 050509c: Optical monitoring
  82. Konus-Wind observation of an intermediate burst from SGR 1806-20
  83. XRF050509c: Radio Detection
  84. GRB 050607 optical decay
  85. GRB050607: refined analysis of prompt REM observations
  86. GRB 050607: PROMPT VRcIc Observations
  87. GRB 050607: Optical decay and spectral slope
  88. GRB050607,optical observation
  89. Optical Afterglow of GRB 050607
  90. GRB050607: Swift Detection of a long GRB
  91. GRB050607: prompt REM observations
  92. Limits on a SN in the field of GRB 050509b
  93. GRB 050603 - XRT data analysis of the first day
  94. GRB050603, submillimetre observations
  95. GRB050603: Radio Detection
  96. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  97. GRB 050603: INTEGRAL shows it is not a short GRB
  98. GRB 050525a, infrared observations
  99. GRB050528, XRT observations
  100. GRB050528: updated Liverpool Telescope limits

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