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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23704 results found.

  1. GRB 050509b: optical observations
  2. GRB 050509b: Swift XRT Position
  3. Swift Detection of GRB050509b: A short duration burst
  4. GRB 050509a: Swift XRT Position
  5. GRB 050505: Keck I-band Magnitude
  6. GRB 050505: early time observations
  7. GRB 050505 - Faulkes Telescope North observations
  8. GRB 050505, simultaneous optical observation
  9. GRB 050505: Further Swift UVOT observations.
  10. GRB050505: AAVSO observations
  11. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  12. GRB 050505 UVOT
  13. GRB050505: Optical Afterglow Candidate
  14. GRB 050505: Swift XRT Position
  15. GRB050505 Swift-BAT refined analysis
  16. GRB 050502a: Optical Observations
  17. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  18. GRB050502b: Afterglow Confirmation
  19. GRB050502: P200 Observations (Correction)
  20. GRB050502: P200 Observations
  21. GRB 050504 : R band observation at Lulin observatory
  22. Swift UVOT observation of GRB 050504
  23. GRB 050504, R band Observations
  24. GRB050504: Faulkes North optical robotic limit
  25. GRB 050502b, V band Observations
  26. GRB 050504: A long GRB detected with INTEGRAL
  27. GRB 050502b, Optical observations
  28. Renewal of SGR 1806-20 activity
  29. GRB050502A: Optical Observations
  30. GRB050502B Swift-BAT refined analysis
  31. GRB 050502a : R band observation at Lulin observatory
  32. GRB 050502b : optical observation at Lulin observatory
  33. Swift Detection of the Bright Burst GRB050502b
  34. GRB 050502: INTEGRAL results
  35. GRB 050502 - A long GRB detected with INTEGRAL
  36. Swift/BAT possible detection of a weak burst GRB050430
  37. GRB 050401: Rc observation
  38. GRB050416a: Radio Detection
  39. GRB 050422: Swift-UVOT observation
  40. GRB 050422: Swift-BAT refined analysis
  41. Swift Detection of GRB 050422
  42. GRB050421: Radio Observations
  43. GRB050421: Radio Observations
  44. GRB 050421: Swift-UVOT observation
  45. GRB 050421: Swift-BAT refined analysis
  46. GRB 050421: NIR observations re-examination
  47. GRB 050421: early Swift XRT analysis results
  48. GRB 050421: NIR observations
  49. GRB 050421: BOOTES-2 simultaneous optical observations
  50. GRB 050421: Optical observations at the INT
  51. Swift Detection of GRB050421
  52. GRB 050418: Swift-BAT refined analysis
  53. Swift-BAT detection of the bright and long GRB 050418
  54. GRB 050416 : optical observation at Xinglong observatory
  55. GRB 050416B: optical observations
  56. GRB 050416b: Swift-BAT refined analysis
  57. GRB050416B: IR observations
  58. Swift-BAT detection of GRB 050416b
  59. GRB050412: Radio Observations
  60. GRB050416: Refined Swift-XRT analysis
  61. GRB050416: Maidanak optical observations
  62. GRB 050416: Swift-BAT refined analysis
  63. GRB050416: P200 NIR Observations
  64. GRB 050416: Radio observations
  65. Confirmation of OT for GRB050416
  66. Swift BAT/XRT Detection of GRB 050416
  67. GRB 050408: RTT150 optical observations
  68. GRB050408: optical observation
  69. GRB 050412: PROMPT VRcIc Observations
  70. GRB 050412: optical limit
  71. GRB 050412: optical observations
  72. GRB 050408: refined XRT analysis, no jet break seen yet
  73. GRB 050412: early Swift XRT analysis results
  74. GRB 050412 : XingLong optical observation
  75. GRB 050412: Swift-BAT refined analysis
  76. GRB 050412: ANU 2.3m observations
  77. GRB 050408: SDSS Field Calibration
  78. GRB 050412: Optical limit
  79. GRB050412: P60 Observations
  80. GRB 050412: Swift XRT Position
  81. GRB050412: ROTSE-III Optical Limits
  82. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  83. GRB 050412: IR and Optical observations
  84. GRB050408: Radio Observations
  85. GRB 050410: Early Optical/Ultraviolet Observations with Swift/UVOT
  86. GRB 050408: PROMPT VRcIc Observations
  87. GRB 050408: Early Optical/Ultraviolet Observations with Swift/UVOT
  88. GRB 050410 R band Optical Observations
  89. GRB050410: Radio Observations
  90. GRB 050408: Swift XRT measurement of possible jet break
  91. GRB050410: MASTER optical observations
  92. GRB 050410: Early observations with Swift-UVOT
  93. Swift-BAT detection of GRB 050410
  94. GRB 050410: Swift XRT Position
  95. GRB 050408: Inconsistency of host galaxy identification
  96. GRB 050408: WIDGET simultaneous optical observations
  97. GRB 050408: SOAR UBVRc Observations
  98. GRB050408: Radio Observations
  99. GRB 050408: Swift XRT analysis
  100. GRB050408: REM NIR and Optical observation

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