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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"

38586 results found.

  1. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  2. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  3. GRB 050509b: Further Analysis of Keck LRIS Images
  4. GRB050509c: REM NIR and Optical observations
  5. GRB 050509b: Physical Properties of the Candidate Host galaxy
  6. GRB 050505: SARA Observations
  7. Swift UVOT Follow-up Observations of GRB 050509B
  8. GRB 050509B, Optical Observations
  9. GRB 050509B: Swift/XRT refined analysis
  10. GRB050509a: Swift UVOT observations
  11. GRB 050509b: Possible Optical Counterpart
  12. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  13. GRB 050509A: Optical observations
  14. GRB 050509b: Optical Counterpart Candidate
  15. GRB050509b: Radio Observations
  16. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  17. GRB 050509b: Swift XRT Position
  18. GRB 050509B: ROTSE-III Optical Limits
  19. Swift Detection of GRB050509b: A short duration burst
  20. GRB 050509a: Swift XRT Position
  21. Swift Detection of the Burst GRB050509
  22. Swift-BAT detection of GRB 050507
  23. GRB 050505: Keck I-band Magnitude
  24. GRB 050505: early time observations
  25. GRB 050505 - Faulkes Telescope North observations
  26. GRB 050502a: Swift XRT Upper Limit
  27. GRB050505: Infrared observations
  28. GRB 050505: Further Swift UVOT observations.
  29. GRB050505: AAVSO observations
  30. GRB050416A : 1 GHz limit from GMRT
  31. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  32. GRB 050505 UVOT
  33. GRB050505: Optical Afterglow Candidate
  34. GRB 050505: Swift XRT Position
  35. GRB050505 Swift-BAT refined analysis
  36. GRB 050502a: Optical Observations
  37. GRB 050416b:Swift XRT afterglow upper limits
  38. GRB 050416b:Swift XRT afterglow upper limits
  39. Swift-BAT detection of GRB050505
  40. GRB 050504: Swift XRT position
  41. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  42. GRB050502b: Afterglow Confirmation
  43. GRB050502: P200 Observations (Correction)
  44. GRB050502: P200 Observations
  45. GRB 050504 : R band observation at Lulin observatory
  46. Swift UVOT observation of GRB 050504
  47. GRB 050504, R band Observations
  48. GRB050504: Faulkes North optical robotic limit
  49. GRB 050502b, V band Observations
  50. GRB050504: P60 Observations
  51. GRB 050504: A long GRB detected with INTEGRAL
  52. GRB 050502b, Optical observations
  53. GRB050502a: P60 Observations (Correction)
  54. GRB050502a: P60 Observations
  55. Renewal of SGR 1806-20 activity
  56. GRB 050502a: RBO Observations
  57. GRB 050502A: WSRT Radio Observations
  58. GRB050502A: Optical Observations
  59. GRB050502B Swift-BAT refined analysis
  60. GRB050502B: I band source in XRT error circle
  61. Swift UVOT refined analysis
  62. Retraction of Swift-BAT trigger 116145
  63. GRB 050502a : R band observation at Lulin observatory
  64. GRB 050502b : optical observation at Lulin observatory
  65. GRB 050502b: Swift XRT Position
  66. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  67. GRB050502B: Optical Limits from ANU 1m
  68. Swift Detection of the Bright Burst GRB050502b
  69. GRB 050502: INTEGRAL results
  70. GRB050502: ANU 1m optical Observations
  71. GRB 050502: Confirmed variability of the afterglow candidate +
  72. GRB 050502: PAIRITEL IR Observations
  73. GRB050502 - Correction on the Optical Candidate from the Liverpool
  74. GRB 050502 - A long GRB detected with INTEGRAL
  75. GRB 050502: ROTSE-III Detection of Possible Counterpart
  76. Swift-BAT Trigger 115881 is not a real GRB
  77. Swift/BAT possible detection of a weak burst GRB050430
  78. GRB 050401: Rc observation
  79. GRB050416a: Radio Detection
  80. GRB 050422: Swift-UVOT observation
  81. GRB 050422: Swift-BAT refined analysis
  82. GRB 050422: Swift XRT Position
  83. Swift Detection of GRB 050422
  84. GRB 050421: NIR observations
  85. GRB 050416: Optical/NIR observations
  86. GRB 050421: SLOTIS observations
  87. GRB 050421: Further Analysis of IR imaging
  88. GRB050421: Radio Observations
  89. GRB050421: Radio Observations
  90. GRB 050421: Swift-UVOT observation
  91. GRB 050421: IR Observations
  92. GRB 050421: Swift-BAT refined analysis
  93. GRB 050421: ROTSE-III Optical Limits
  94. GRB 050421: NIR observations re-examination
  95. GRB050421
  96. GRB 050421: early Swift XRT analysis results
  97. GRB 050421: NIR observations
  98. GRB050421: P60 Observations
  99. GRB 050421: Optical observations at the INT
  100. Swift Detection of GRB050421

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