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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').

17828 results found.

  1. GRB060210: Early Optical Observations
  2. GRB060210:Faulkes Telescope North Afterglow Confirmation
  3. GRB 060210: candidate afterglow
  4. GRB 060210: Swift detection of a burst
  5. GRB060210: Optical afterglow
  6. GRB 060206: Swift/UVOT Observations
  7. Swift-BAT trigger 180931 is not a GRB
  8. GRB060209: RTT150 optical observations
  9. GRB 060209 : TAROT optical observation
  10. GRB 060209(?): Swift-BAT detection of a possible burst
  11. GRB 060206: WSRT Radio Observations
  12. GRB 060203: Swift/UVOT upper limits
  13. GRB060204a: Swift XRT Source is not GRB Afterglow
  14. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  15. GRB 060204A: ROSAT Pointing
  16. GRB060204A: Swift/UVOT observations
  17. GRB 060206: Swift-BAT refined analysis
  18. GRB060206: Swift XRT Refined Analysis
  19. GRB060206: Swift XRT Position
  20. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  21. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  22. GRB060206: Swift-BAT detection of a burst
  23. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  24. BAT GRB 060204C is probably not a GRB
  25. GRB 060204B: BVRi-band detections of optical afterglow
  26. GRB 060204A: Swift XRT upper limit
  27. GRB060204B: Swift/UVOT refined analysis
  28. Swift XRT Observation of GRB 060204C
  29. GRB 060204B: Swift-BAT refined analysis
  30. GRB060204B: Swift XRT Team Refined Analysis
  31. GRB 060204C: OSN limits
  32. GRB 060204C: Liverpool Telescopes optical limit
  33. GRB 060204C: ROTSE-III Optical Limits
  34. GRB 060204C: Swift-BAT detection of a burst
  35. GRB 060124: Radio Observations
  36. GRB060204B: Faulkes OT candidate
  37. GRB060204B, optical observation
  38. GRB060204B - SDSS pre-burst observations
  39. GRB 060203: Swift-BAT refined analysis
  40. GRB 060204B: Swift detection of a burst
  41. GRB 060203: RTT150 optical observations
  42. GRB060203: Swift XRT Team Refined Analysis
  43. GRB060203 - Swift UVOT observation
  44. Swift-BAT trigger is GRB 060203
  45. GRB060203: Observations with SARA
  46. GRB 060203: P60 Confirmation of Optical Afterglow
  47. Possible GRB 060203: candidate optical counterpart
  48. Swift BAT Trigger 180151: Swift XRT source detection
  49. Possible GRB 060203: optical observations at Asiago
  50. Swift-BAT trigger 180151 is unknown origin at this time
  51. GRB 060202: Refined analysis of the Swift-BAT burst
  52. GRB060202, optical observation
  53. GRB 060202: Swift/UVOT upper limits
  54. GRB 060202: Swift XRT Team Refined Analysis
  55. GRB060202: Faulkes North observation
  56. GRB 060202: Swift detection of a burst
  57. GRB 060130: Swift/XRT observation
  58. GRB 060123: VLA Radio Observations
  59. Possible GRB 051221B: MDM Correction
  60. GRB 060123: Swift refined analysis of an unusual GRB
  61. GRB060124, BVRcIc field calibration
  62. GRB060105: refined analysis of the Suzaku observation
  63. GRB 060124: HETE detection and spectrum of the main peak
  64. Konus-Wind observation of GRB 060124
  65. GRB060124: detailed XRT analysis
  66. GRB 060124 Optical Observations
  67. GRB 060124: R band Observations
  68. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  69. GRB 060123: Swift detection of a very long, faint burst
  70. GRB 060124: TAROT optical limits
  71. GRB 060124: Swift/UVOT Observation
  72. GRB 060124: Confirmation of the Afterglow
  73. GRB 060124: XRT position
  74. GRB 060124: Optical Observations at Tautenburg
  75. GRB 060117: Suzaku WAM observation of the prompt emission
  76. GRB060124:MASTER optical observation
  77. GRB 060111B: Suzaku WAM observation of the prompt emission
  78. GRB 060124: Swift-BAT detection of a burst
  79. GRB 060116: Radio Detection
  80. GRB 060116: MARGE optical observations
  81. GRB 060121: Swift/UVOT upper limits
  82. GRB 060121: Liverpool Telescopes optical limits
  83. GRB 060121: Swift XRT refined analysis
  84. GRB 060121: Swift XRT refined position
  85. GRB 060117: pseudo-z from spectral parameters of the prompt emission
  86. Konus-Wind observation of GRB 060117
  87. GRB 060117: Refined analysis of the Swift-BAT burst
  88. GRB 060117: FRAM optical afterglow candidate
  89. GRB 060117: Swift-BAT detection of a bright burst
  90. GRB 060116: Refined analysis of the Swift-BAT burst
  91. GRB 060116: Swift/UVOT upper limits
  92. GRB060115: REM observations
  93. GRB 060110: XRT position and analysis
  94. GRB 060116: ROTSE-III Optical Limits
  95. GRB060116: XRT position
  96. GRB060116: Faulkes North observation
  97. GRB 060116: Swift-BAT detection of a burst
  98. GRB 060115: Refined analysis of the Swift-BAT burst
  99. GRB 060115: Swift/UVOT upper limits
  100. GRB 060115: Swift XRT refined analysis

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