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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"

28043 results found.

  1. GRB 050709: Refined Spectral and Temporal Properties
  2. GRB050714b: Radio Observation
  3. GRB050712: Radio Observations
  4. GRB050713a: Radio Observation
  5. GRB 050712, Tautenburg optical afterglow observations
  6. Swift-BAT detection of a possible GRB
  7. GRB 050714B: VLT R-band observations
  8. GRB 050717: Additional LCO observations
  9. GRB 050716; J-band observations
  10. GRB 050717: LCO near-IR observations
  11. Swift/UVOT Observations of GRB 050717
  12. GRB 050717: Swift-BAT refined analysis
  13. GRB050717: Swift XRT position
  14. Swift detection of GRB 050717
  15. Swift UVOT Observations of GRB 050716
  16. GRB 050716: Refined XRT analysis.
  17. GRB050716: Refined analysis of the Swift-BAT burst
  18. GRB 050716: Lulin B and R band optical observations
  19. GRB050716, optical observation
  20. GRB050716: Faulkes North Telescope observation
  21. GRB050715: Refined analysis of the Swift-BAT burst
  22. GRB 050715: Swift-BAT detection
  23. GRB 050713b: RTT150 optical observations
  24. GRB050714B: Refined analysis of the Swift-BAT burst
  25. GRB 050714B: optical afterglow
  26. GRB 050714, R-band candidate
  27. GRB 050714, optical observations
  28. GRB 050713A: XRT refined analysis
  29. GRB 050713A: RAPTOR detection of early optical emission
  30. GRB050713B :Swift/UVOT observations
  31. GRB050713b: XRT refined analysis
  32. GRB050712: TNG R-band observations
  33. GRB 050713B: Swift-BAT Refined Analysis
  34. GRB 050713A: Swift/UVOT observation
  35. GRB 050713A : Swift-BAT Refined Analysis
  36. GRB050712: Swift UVOT Observation of Afterglow Emission
  37. GRB 050713A : Lulin R-band observation
  38. GRB 050713A XMM-Newton observation
  39. GRB 050713b : Lulin R-band observations
  40. GRB050713B: Faulkes North Telescope observation
  41. RBO RI observations of GRB 050713A
  42. GRB 050713B
  43. GRB050709 : Chandra source optical counterpart
  44. GRB050713: Liverpool Telescope prompt observations
  45. GRB 050712, optical observations
  46. GRB050709: Candidate X-ray Afterglow from Chandra
  47. GRB050713: possible I-band afterglow
  48. GRB050712: XRT refined analysis
  49. GRB050709: Radio Observations
  50. GRB 050709: Swift UVOT and XRT observations
  51. GRB 050712: Swift-BAT Refined Analysis
  52. GRB050712: UVOT candidate optical counterpart
  53. GRB 050709: LCO40 Observations
  54. GRB050709, optical observations
  55. PROMPT Rc Observations of GRB 050709
  56. GRB 050525a: PROMPT VRcIc Detections
  57. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  58. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  59. GRB 050626: Swift XRT observations
  60. GRB 050408: ARC 3.5-meter NIR Observations
  61. GRB 050701: Refined XRT analysis
  62. Swift UVOT observations of GRB 050701
  63. GRB050701: Swift-BAT Refined analysis
  64. Swift trigger 143708 is really GRB 050701
  65. GRB 050607, radio observations
  66. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  67. GRB050525a: HST Observations
  68. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  69. XRF 050509c: Optical monitoring
  70. Konus-Wind observation of an intermediate burst from SGR 1806-20
  71. XRF050509c: Radio Detection
  72. GRB 050607 optical decay
  73. GRB050607: refined analysis of prompt REM observations
  74. GRB 050607: PROMPT VRcIc Observations
  75. GRB 050607: Optical decay and spectral slope
  76. GRB050607,optical observation
  77. Optical Afterglow of GRB 050607
  78. GRB050607: Swift Detection of a long GRB
  79. GRB050607: prompt REM observations
  80. Limits on a SN in the field of GRB 050509b
  81. GRB 050603 - XRT data analysis of the first day
  82. GRB050603, submillimetre observations
  83. GRB050603: Radio Detection
  84. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  85. GRB 050603: INTEGRAL shows it is not a short GRB
  86. GRB 050525a, infrared observations
  87. GRB050528, XRT observations
  88. GRB050528: updated Liverpool Telescope limits
  89. Swift-BAT GRB 050528: a soft burst
  90. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  91. Possible GRB050528: no candidate from Liverpool Telescope
  92. GRB050525a: Radio Observations
  93. GRB 050509b: refined XRT/Chandra afterglow position analysis
  94. GRB 050525: RTT150, Optical observations
  95. GRB 050525a: SARA Observations
  96. GRB 050525B: Swift-BAT observations
  97. GRB 050525: MITSuME Optical Observation in VRI
  98. GRB050525A,optical observation
  99. GRB050525: Super-LOTIS observations
  100. GRB 050525, spectral lag pseudo-redshift

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