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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"

37226 results found.

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

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