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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"
  1. GRB 050421: ROTSE-III Optical Limits
  2. GRB 050421: NIR observations re-examination
  3. GRB050421
  4. GRB 050421: early Swift XRT analysis results
  5. GRB 050421: NIR observations
  6. GRB050421: P60 Observations
  7. GRB 050421: BOOTES-2 simultaneous optical observations
  8. GRB 050421: Optical observations at the INT
  9. Swift Detection of GRB050421
  10. GRB 050416b: Tentative Swift XRT Position
  11. GRB 050315: potential host galaxy
  12. GRB050326: analysis of the XMM-Newton observation
  13. GRB050418: Null Optical Observations
  14. GRB 050412: Chandra observations
  15. GRB050416A, optical observations
  16. GRB 050418: Swift-BAT refined analysis
  17. Swift-BAT detection of the bright and long GRB 050418
  18. GRB 050416: Mitsume optical observation
  19. GRB 050416 : optical observation at Xinglong observatory
  20. GRB 050416B: optical observations
  21. GRB 050416b: Swift-BAT refined analysis
  22. GRB 050416b: LCO observations
  23. GRB 050416b: LCO observations
  24. GRB050416B: IR observations
  25. GRB 050416: Swift/UVOT refined analysis
  26. Swift-BAT detection of GRB 050416b
  27. IBAS GRB Alert # 2463: not a GRB
  28. GRB050412: Radio Observations
  29. GRB 050416: Swift/UVOT detection of afterglow emission
  30. GRB050416: Refined Swift-XRT analysis
  31. GRB050416: Maidanak optical observations
  32. GRB 050416: Swift-BAT refined analysis
  33. GRB 050416: ART observations
  34. GRB 050416,optical observation
  35. GRB 050416: KAIT observations
  36. GRB050416: P200 NIR Observations
  37. GRB 050416: Swift XRT Position
  38. GRB 050416: Radio observations
  39. Confirmation of OT for GRB050416
  40. GRB050416: P60 Afterglow Candidate
  41. Swift BAT/XRT Detection of GRB 050416
  42. GRB 050412: Subaru observations
  43. GRB 050408: RTT150 optical observations
  44. GRB050408: optical observation
  45. GRB 050412: PROMPT VRcIc Observations
  46. GRB 050408: Kuiper 1.5m observations
  47. GRB 050412: optical limit
  48. GRB 050412: optical observations
  49. GRB 050408: refined XRT analysis, no jet break seen yet
  50. GRB 050412: early Swift XRT analysis results
  51. GRB 050412 : XingLong optical observation
  52. GRB 050412: Swift-BAT refined analysis
  53. GRB 050412: ANU 2.3m observations
  54. GRB 050412: Early Optical/Ultraviolet Observations with
  55. GRB 050412: retraction of UVOT transient report
  56. GRB 050412: UVOT transient not in XRT error circle
  57. GRB 050408: SDSS Field Calibration
  58. GRB 050412: Optical limit
  59. GRB 050412: LCO Optical Observations
  60. GRB 050412: Optical observations
  61. GRB050412: P60 Observations
  62. GRB 050412: Swift XRT Position
  63. GRB050412: optical limit before and during GRB
  64. GRB 050412: LCO optical observations
  65. GRB050412: ROTSE-III Optical Limits
  66. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  67. GRB 050412: IR and Optical observations
  68. GRB 050412: IR Observations
  69. GRB050408: Radio Observations
  70. GRB 050401: Optical limit
  71. GRB 050408: Optical limit
  72. GRB050410: P60 Observations
  73. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  74. GRB 050410, optical observations
  75. GRB 050408: PROMPT VRcIc Observations
  76. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  77. GRB 050410 R band Optical Observations
  78. GRB050410 : Null detection report
  79. GRB 050410, optical observations
  80. GRB050410: Radio Observations
  81. GRB 050408: Swift XRT measurement of possible jet break
  82. GRB050410: MASTER optical observations
  83. GRB 050410: Early observations with Swift-UVOT
  84. Swift-BAT detection of GRB 050410
  85. GRB 050410: Swift XRT Position
  86. GRB 050408: Retraction of Proposed Host Galaxy
  87. GRB 050408: Inconsistency of host galaxy identification
  88. GRB 050408: Subaru Observations
  89. GRB 050408: WIDGET simultaneous optical observations
  90. GRB 050408: SOAR UBVRc Observations
  91. GRB 050408: Properties of the Host Galaxy
  92. GRB 050408: Mercator Optical Observations
  93. GRB050408: Radio Observations
  94. GRB 050408: Swift XRT analysis
  95. GRB 050408, SMARTS optical/IR afterglow observations
  96. GRB 050408: Optical limit at 20 min after the burst
  97. GRB 050408, optical observations
  98. GRB050408: REM NIR and Optical observation
  99. GRB 050408: Moderate-resolution Gemini Spectroscopy
  100. GRB 050408,optical observation

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