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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

18345 results found.

  1. GRB050306: optical afterglow not confirmed
  2. GRB 050525A: BOOTES simultaneous optical observations
  3. GRB 050525A: Swift-BAT refined analysis
  4. Swift/UVOT UV and optical detections of GRB 050525
  5. Konus-Wind observation of GRB 050525
  6. GRB 050525: TAROT observations of the early afterglow
  7. INTEGRAL detection of GRB 050525
  8. GRB 050525: Optical observation
  9. GRB050525: ROTSE-III Refined Analysis
  10. GRB 050525 - Very Bright, Not Short
  11. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  12. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  13. XRF 050522: Swift XRT refined analysis
  14. Swift/UVOT observation of XRF 050522
  15. GRB 050509A: Further I-band imaging
  16. RBO Observations of GRB050522
  17. XRF 050522: Swift XRT observation
  18. GRB 050520: VLT/ULTRACAM observations
  19. Swift UVOT Observations of GRB 050520
  20. GRB 050520: Swift XRT refined analysis
  21. XRF050509C: Chandra Afterglow Detection
  22. XRF 050509c: Swift XRT Upper Limit
  23. RBO Observations of GRB050520
  24. GRB 050520: TAROT optical limit
  25. GRB 050520: Swift XRT position
  26. No Swift-BAT Lightcurves in real-time for next 3 weeks
  27. Swift-BAT trigger 122203 is not a real GRB
  28. GRB 050504: Swift XRT afterglow candidate has faded
  29. GRB 050509B: Subaru Optical Observations
  30. GRB050502b: Early Observation
  31. Refined Chandra analysis of GRB 050509b
  32. GRB050509b, SDSS pre-burst observations
  33. Chandra observation of GRB 050509b
  34. GRB 050509b: RAPTOR deep, early limits.
  35. GRB050509B: Optical/Infared observations
  36. GRB 050509b: Swift/UVOT follow-up measurements
  37. GRB 050509b Milagro GeV/TeV Observations
  38. GRB050509B: Optical observations at the Very Large Telescope
  39. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  40. GRB 050509a: Swift-BAT refined analysis
  41. GRB 050509B: WSRT Radio Observations
  42. GRB 050505: SARA Observations
  43. Swift UVOT Follow-up Observations of GRB 050509B
  44. GRB 050509B, Optical Observations
  45. GRB 050509B: Swift/XRT refined analysis
  46. GRB050509a: Swift UVOT observations
  47. GRB 050509b: Optical observations
  48. GRB 050509b: Possible Optical Counterpart
  49. GRB 050509A: Optical observations
  50. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  51. GRB 050509b: optical observations
  52. GRB 050509b: Swift XRT Position
  53. GRB 050509B: ROTSE-III Optical Limits
  54. Swift Detection of GRB050509b: A short duration burst
  55. GRB 050509a: Swift XRT Position
  56. Swift Detection of the Burst GRB050509
  57. Swift-BAT detection of GRB 050507
  58. GRB 050505: early time observations
  59. GRB 050505 - Faulkes Telescope North observations
  60. GRB 050502a: Swift XRT Upper Limit
  61. GRB 050505, simultaneous optical observation
  62. GRB 050505: Further Swift UVOT observations.
  63. GRB050416A : 1 GHz limit from GMRT
  64. GRB 050505 UVOT
  65. GRB 050505: Swift XRT Position
  66. GRB050505 Swift-BAT refined analysis
  67. GRB 050416b:Swift XRT afterglow upper limits
  68. GRB 050416b:Swift XRT afterglow upper limits
  69. Swift-BAT detection of GRB050505
  70. GRB 050504: Swift XRT position
  71. Swift UVOT observation of GRB 050504
  72. GRB 050502b, V band Observations
  73. GRB050502B Swift-BAT refined analysis
  74. GRB050502B: I band source in XRT error circle
  75. Swift UVOT refined analysis
  76. Retraction of Swift-BAT trigger 116145
  77. GRB 050502b : optical observation at Lulin observatory
  78. GRB 050502b: Swift XRT Position
  79. GRB050502B: Optical Limits from ANU 1m
  80. Swift Detection of the Bright Burst GRB050502b
  81. GRB050502: ANU 1m optical Observations
  82. Swift-BAT Trigger 115881 is not a real GRB
  83. Swift/BAT possible detection of a weak burst GRB050430
  84. GRB 050401: Rc observation
  85. GRB050416a: Radio Detection
  86. GRB 050422: Swift-UVOT observation
  87. GRB 050422: Swift-BAT refined analysis
  88. GRB 050422: Swift XRT Position
  89. Swift Detection of GRB 050422
  90. GRB 050421: SLOTIS observations
  91. GRB050421: Radio Observations
  92. GRB050421: Radio Observations
  93. GRB 050421: Swift-UVOT observation
  94. GRB 050421: Swift-BAT refined analysis
  95. GRB 050421: ROTSE-III Optical Limits
  96. GRB 050421: early Swift XRT analysis results
  97. GRB 050421: BOOTES-2 simultaneous optical observations
  98. GRB 050421: Optical observations at the INT
  99. Swift Detection of GRB050421
  100. GRB 050416b: Tentative Swift XRT Position

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