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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"

32719 results found.

  1. GRB 050509B: ROTSE-III Optical Limits
  2. GRB 050509a: Swift XRT Position
  3. GRB 050505: Keck I-band Magnitude
  4. GRB 050505: early time observations
  5. GRB 050502a: Swift XRT Upper Limit
  6. GRB 050505, simultaneous optical observation
  7. GRB050505: Infrared observations
  8. GRB 050505: Further Swift UVOT observations.
  9. GRB050505: AAVSO observations
  10. GRB050416A : 1 GHz limit from GMRT
  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. GRB 050416b:Swift XRT afterglow upper limits
  18. GRB 050416b:Swift XRT afterglow upper limits
  19. Swift-BAT detection of GRB050505
  20. GRB 050504: Swift XRT position
  21. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  22. GRB050502b: Afterglow Confirmation
  23. GRB050502: P200 Observations (Correction)
  24. GRB050502: P200 Observations
  25. GRB 050504 : R band observation at Lulin observatory
  26. Swift UVOT observation of GRB 050504
  27. GRB 050504, R band Observations
  28. GRB050504: P60 Observations
  29. GRB 050502b, Optical observations
  30. GRB050502a: P60 Observations (Correction)
  31. GRB050502a: P60 Observations
  32. GRB 050502a: RBO Observations
  33. GRB 050502A: WSRT Radio Observations
  34. GRB050502A: Optical Observations
  35. GRB050502B Swift-BAT refined analysis
  36. GRB050502B: I band source in XRT error circle
  37. Swift UVOT refined analysis
  38. Retraction of Swift-BAT trigger 116145
  39. GRB 050502a : R band observation at Lulin observatory
  40. GRB 050502b : optical observation at Lulin observatory
  41. GRB 050502b: Swift XRT Position
  42. GRB050502B: Optical Limits from ANU 1m
  43. GRB 050502: INTEGRAL results
  44. GRB050502: ANU 1m optical Observations
  45. GRB 050502: Confirmed variability of the afterglow candidate +
  46. GRB 050502: PAIRITEL IR Observations
  47. GRB 050502: ROTSE-III Detection of Possible Counterpart
  48. Swift-BAT Trigger 115881 is not a real GRB
  49. Swift/BAT possible detection of a weak burst GRB050430
  50. GRB 050401: Rc observation
  51. GRB050416a: Radio Detection
  52. GRB 050422: Swift-UVOT observation
  53. GRB 050422: Swift-BAT refined analysis
  54. GRB 050422: Swift XRT Position
  55. GRB 050421: NIR observations
  56. GRB 050416: Optical/NIR observations
  57. GRB 050421: SLOTIS observations
  58. GRB 050421: Further Analysis of IR imaging
  59. GRB050421: Radio Observations
  60. GRB050421: Radio Observations
  61. GRB 050421: Swift-UVOT observation
  62. GRB 050421: IR Observations
  63. GRB 050421: Swift-BAT refined analysis
  64. GRB 050421: ROTSE-III Optical Limits
  65. GRB 050421: NIR observations re-examination
  66. GRB050421
  67. GRB 050421: early Swift XRT analysis results
  68. GRB 050421: NIR observations
  69. GRB050421: P60 Observations
  70. GRB 050421: BOOTES-2 simultaneous optical observations
  71. GRB 050421: Optical observations at the INT
  72. Swift Detection of GRB050421
  73. GRB 050416b: Tentative Swift XRT Position
  74. GRB 050315: potential host galaxy
  75. GRB050418: Null Optical Observations
  76. GRB 050412: Chandra observations
  77. GRB050416A, optical observations
  78. GRB 050418: Swift-BAT refined analysis
  79. GRB 050416: Mitsume optical observation
  80. GRB 050416 : optical observation at Xinglong observatory
  81. GRB 050416B: optical observations
  82. GRB 050416b: Swift-BAT refined analysis
  83. GRB 050416b: LCO observations
  84. GRB 050416b: LCO observations
  85. GRB050416B: IR observations
  86. GRB 050416: Swift/UVOT refined analysis
  87. GRB050412: Radio Observations
  88. GRB 050416: Swift/UVOT detection of afterglow emission
  89. GRB050416: Refined Swift-XRT analysis
  90. GRB 050416: Swift-BAT refined analysis
  91. GRB 050416: ART observations
  92. GRB 050416: KAIT observations
  93. GRB050416: P200 NIR Observations
  94. GRB 050416: Swift XRT Position
  95. GRB 050416: Radio observations
  96. GRB 050412: Subaru observations
  97. GRB 050408: RTT150 optical observations
  98. GRB050408: optical observation
  99. GRB 050412: PROMPT VRcIc Observations
  100. GRB 050408: Kuiper 1.5m observations

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