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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').

18177 results found.

  1. GRB 050827: Swift-BAT refined analysis
  2. GRB050827: Swift-BAT detection of a burst
  3. GRB 050826: Optical Candidate
  4. GRB050824, HETE-2 Observation
  5. GRB 050826: Swift XRT preliminary analysis results
  6. GRB 050826: BAT refined analysis
  7. GRB050826: Swift/UVOT early upper limits
  8. GRB050824: First 2 hours of power low optical decay?
  9. GRB 050826: Swift XRT position
  10. GRB050826: Swift-BAT detection of a long burst
  11. GRB050824: MASTER final analysis of the OT observations
  12. Possible GRB050825:MASTER optical observations
  13. Swift-BAT trigger 152038 is definitely not a GRB
  14. GRB050824: CORRECTION to UVOT observing times
  15. Swift-BAT trigger 152038 is probably not a GRB
  16. GRB050824: Swift/UVOT detection of fading afterglow
  17. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  18. GRB050824, I-band imaging
  19. GRB 050822: refined XRT analysis
  20. GRB 050824: XRT refined analysis and possible afterglow detection
  21. GRB 050824: BAT refined analysis of a soft weak burst
  22. GRB050824: MASTER:OT decay
  23. GRB050824: MASTER observation OT
  24. GRB050805a: MASTER optical candidat
  25. GRB 050824: ROTSE-III Optical Limits
  26. GRB050824: Swift-BAT detection of a burst
  27. GRB050822: Swift/UVOT upper limits
  28. GRB 050820A BAT observations of second, larger episode of emission
  29. GRB 050822: Swift-BAT refined analysis
  30. GRB 050820a - corrections to GCN 3846
  31. Swift/UVOT UV Photometry of GRB 050820B
  32. GRB 050822: ROTSE-III Prompt Optical Limits
  33. GRB 050822: Swift detection of a long burst
  34. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  35. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  36. GRB050820a BVRcIc field photometry
  37. GRB050820B XMM-Newton observation
  38. GRB 050820a: NIR Observations by WIRO
  39. GRB 050820B: Swift XRT position
  40. SUBJECT: GRB050820B: Refined analysis of the Swift-BAT burst
  41. GRB050820B: BAT-Swift detection of a bright GRB
  42. Swift/UVOT photometry of GRB050820
  43. GRB050820: refined XRT analysis
  44. GRB 050820: Early RAPTOR detections
  45. GRB 050820 Swift-BAT refined analysis
  46. GRB050819: refined XRT analysis
  47. GRB 050820: Swift detection of a GRB
  48. GRB050820: Optical afterglow from P60
  49. GRB 050819 Swift-BAT refined analysis
  50. GRB050819: Swift XRT position
  51. GRB050819: Swift-BAT detection of a weak burst
  52. Swift-BAT trigger 150993 is not a GRB
  53. Swift Trigger 150823 is HETE J1900.1-2455
  54. GRB050817: Swift-BAT Detection of a burst
  55. GRB050815: Optical afterglow detection by Swift UVOT
  56. GRB050815: XRT refined analysis
  57. GRB050815: Refined analysis of the Swift-BAT burst
  58. GRB 050815: ROTSE-III Optical Limits
  59. GRB050815: Swift XRT afterglow localization
  60. GRB050815: Swift-BAT detection of a burst
  61. GRB050814: P60 Optical Afterglow Candidate
  62. GRB 050814: XRT refined analysis
  63. GRB050814: SWIFT/UVOT observation
  64. GRB050814: Refined analysis of the Swift-BAT burst
  65. GRB 050814: Swift XRT Afterglow Localization
  66. GRB 050814: Swift detection of a burst
  67. GRB050813, SDSS pre-burst observations
  68. GRB 050813: KAIT optical limit
  69. GRB 050813: Swift-BAT refined analysis
  70. GRB050813: SWIFT/UVOT observation
  71. GRB 050813: Swift XRT afterglow localization
  72. GRB 050813: Possible Short Swift-BAT GRB
  73. GRB050813 (Swift 150139): P60 Observations
  74. Swift-BAT trigger 150131 is not a GRB
  75. GRB050805b: CrAO optical limit
  76. GRB050805a : Null detection report
  77. Swift-BAT trigger 149118 is very likely not a GRB
  78. Retraction of Swift Trigger 149131 (GRB 050805B)
  79. GRB 050805b: OHP optical limits
  80. GRB 050805b: TAROT optical limits
  81. GRB050805b: MASTER optical observations
  82. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  83. GRB050805a: MASTER optical candidat
  84. Swift-BAT trigger 149118 is probably not a GRB
  85. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  86. GRB 050803: Swift-BAT refined analysis
  87. GRB050803: MASTER further analys
  88. GRB 050803: early Swift XRT analysis results
  89. GRB 050803: TAROT optical limits
  90. GRB050803: MASTER optical observations
  91. GRB050803: Swift-BAT detection of a very long burst
  92. GCN GRB observation 050713A
  93. GRB 050802: Swift/UVOT optical and UV detections
  94. GRB050802 radio non-detection
  95. GRB 050730: OHP optical observations
  96. GRB 050802: early Swift XRT analysis results
  97. GRB 050802: Swift/UVOT observations
  98. GRB 050802: Swift-BAT refined analysis
  99. GRB 050802: XRT position
  100. GRB 050802: Swift Gamma-ray Burst

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