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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"

37221 results found.

  1. GRB 050509A: Optical observations
  2. GRB 050509b: Optical Counterpart Candidate
  3. GRB 050509b: PAIRITEL and WIYN Observations
  4. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  5. GRB 050509b: optical observations
  6. GRB 050509b: Swift XRT Position
  7. GRB 050509B: ROTSE-III Optical Limits
  8. Swift Detection of GRB050509b: A short duration burst
  9. GRB 050509a: Swift XRT Position
  10. Swift Detection of the Burst GRB050509
  11. Swift-BAT detection of GRB 050507
  12. GRB 050505: Keck I-band Magnitude
  13. GRB 050505: early time observations
  14. GRB 050505 - Faulkes Telescope North observations
  15. GRB 050502a: Swift XRT Upper Limit
  16. GRB 050505, simultaneous optical observation
  17. GRB 050505: Further Swift UVOT observations.
  18. GRB050505: AAVSO observations
  19. GRB050416A : 1 GHz limit from GMRT
  20. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  21. GRB 050505 UVOT
  22. GRB050505: Optical Afterglow Candidate
  23. GRB 050505: Swift XRT Position
  24. GRB 050502a: Optical Observations
  25. GRB 050416b:Swift XRT afterglow upper limits
  26. GRB 050416b:Swift XRT afterglow upper limits
  27. GRB 050504: Swift XRT position
  28. GRB050502: P200 Observations (Correction)
  29. GRB050502: P200 Observations
  30. GRB 050504 : R band observation at Lulin observatory
  31. Swift UVOT observation of GRB 050504
  32. GRB 050504, R band Observations
  33. GRB 050502b, V band Observations
  34. GRB050504: P60 Observations
  35. GRB 050504: A long GRB detected with INTEGRAL
  36. GRB (?) 050504: IR Observations, Intriguing Source
  37. GRB 050502b, Optical observations
  38. GRB050502a: P60 Observations (Correction)
  39. GRB050502a: P60 Observations
  40. Renewal of SGR 1806-20 activity
  41. GRB 050502a: RBO Observations
  42. GRB 050502A: WSRT Radio Observations
  43. GRB050502A: Optical Observations
  44. Swift UVOT refined analysis
  45. Retraction of Swift-BAT trigger 116145
  46. GRB 050502a : R band observation at Lulin observatory
  47. GRB 050502b : optical observation at Lulin observatory
  48. GRB 050502b: Swift XRT Position
  49. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  50. Swift Detection of the Bright Burst GRB050502b
  51. GRB 050502: INTEGRAL results
  52. GRB050502: ANU 1m optical Observations
  53. GRB 050502: Confirmed variability of the afterglow candidate +
  54. GRB 050502: PAIRITEL IR Observations
  55. GRB050502 - Correction on the Optical Candidate from the Liverpool
  56. GRB 050502 - A long GRB detected with INTEGRAL
  57. GRB 050502: ROTSE-III Detection of Possible Counterpart
  58. Swift-BAT Trigger 115881 is not a real GRB
  59. Swift/BAT possible detection of a weak burst GRB050430
  60. GRB 050401: Rc observation
  61. GRB050416a: Radio Detection
  62. GRB 050422: Swift-UVOT observation
  63. GRB 050422: Swift-BAT refined analysis
  64. GRB 050422: Swift XRT Position
  65. Swift Detection of GRB 050422
  66. GRB 050421: NIR observations
  67. GRB 050416: Optical/NIR observations
  68. GRB 050421: SLOTIS observations
  69. GRB 050421: Further Analysis of IR imaging
  70. GRB050421: Radio Observations
  71. GRB050421: Radio Observations
  72. GRB 050421: Swift-UVOT observation
  73. GRB 050421: IR Observations
  74. GRB 050421: Swift-BAT refined analysis
  75. GRB 050421: ROTSE-III Optical Limits
  76. GRB 050421: NIR observations re-examination
  77. GRB 050421: early Swift XRT analysis results
  78. GRB 050421: NIR observations
  79. GRB050421: P60 Observations
  80. GRB 050421: BOOTES-2 simultaneous optical observations
  81. GRB 050421: Optical observations at the INT
  82. GRB 050416b: Tentative Swift XRT Position
  83. GRB 050315: potential host galaxy
  84. GRB 050412: Chandra observations
  85. GRB050416A, optical observations
  86. GRB 050418: Swift-BAT refined analysis
  87. Swift-BAT detection of the bright and long GRB 050418
  88. GRB 050416: Mitsume optical observation
  89. GRB 050416 : optical observation at Xinglong observatory
  90. GRB 050416B: optical observations
  91. GRB 050416b: Swift-BAT refined analysis
  92. GRB 050416b: LCO observations
  93. GRB 050416b: LCO observations
  94. GRB050416B: IR observations
  95. GRB 050416: Swift/UVOT refined analysis
  96. Swift-BAT detection of GRB 050416b
  97. IBAS GRB Alert # 2463: not a GRB
  98. GRB050412: Radio Observations
  99. GRB 050416: Swift/UVOT detection of afterglow emission
  100. GRB050416: Refined Swift-XRT analysis

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