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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. GRB050819: Swift-BAT detection of a weak burst
  2. Swift-BAT trigger 150993 is not a GRB
  3. Swift Trigger 150823 is HETE J1900.1-2455
  4. GRB050817: Swift-BAT Detection of a burst
  5. GRB050815: Optical afterglow detection by Swift UVOT
  6. GRB050815: XRT refined analysis
  7. GRB050815: Refined analysis of the Swift-BAT burst
  8. GRB 050815: ROTSE-III Optical Limits
  9. GRB050815: Swift XRT afterglow localization
  10. GRB050815: Swift-BAT detection of a burst
  11. GRB050814: P60 Optical Afterglow Candidate
  12. GRB 050814: XRT refined analysis
  13. GRB050814: SWIFT/UVOT observation
  14. GRB050814: Refined analysis of the Swift-BAT burst
  15. GRB 050814: Swift XRT Afterglow Localization
  16. GRB 050814: Swift detection of a burst
  17. GRB050813, SDSS pre-burst observations
  18. GRB 050813: KAIT optical limit
  19. GRB 050813: Swift-BAT refined analysis
  20. GRB050813: SWIFT/UVOT observation
  21. GRB 050813: Swift XRT afterglow localization
  22. GRB 050813: Possible Short Swift-BAT GRB
  23. GRB050813 (Swift 150139): P60 Observations
  24. Swift-BAT trigger 150131 is not a GRB
  25. GRB050805b: CrAO optical limit
  26. GRB050805a : Null detection report
  27. Swift-BAT trigger 149118 is very likely not a GRB
  28. Retraction of Swift Trigger 149131 (GRB 050805B)
  29. GRB 050805b: OHP optical limits
  30. GRB 050805b: TAROT optical limits
  31. GRB050805b: MASTER optical observations
  32. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  33. GRB050805a: MASTER optical candidat
  34. Swift-BAT trigger 149118 is probably not a GRB
  35. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  36. GRB 050803: Swift-BAT refined analysis
  37. GRB050803: MASTER further analys
  38. GRB 050803: early Swift XRT analysis results
  39. GRB 050803: TAROT optical limits
  40. GRB050803: MASTER optical observations
  41. GRB050803: Swift-BAT detection of a very long burst
  42. GCN GRB observation 050713A
  43. GRB 050802: Swift/UVOT optical and UV detections
  44. GRB050802 radio non-detection
  45. GRB 050730: OHP optical observations
  46. GRB 050802: early Swift XRT analysis results
  47. GRB 050802: Swift/UVOT observations
  48. GRB 050802: Swift-BAT refined analysis
  49. GRB 050802: XRT position
  50. GRB 050802: Swift Gamma-ray Burst
  51. GRB050801: Swift/UVOT Optical and UV detections
  52. GCN 050801: early Swift XRT analysis results
  53. GRB 050801: Swift-BAT refined analysis
  54. GRB 050801, afterglow observations
  55. GRB 050730, corrected photometry and break?
  56. GRB 050801: ROTSE-III Early Afterglow Break
  57. GRB050801: Swift-BAT detection of a burst
  58. GRB050801: GCN XRT position is incorrect
  59. GRB 050801: ROTSE-III Detection of Possible Counterpart
  60. GRB 050730: XRT refined analysis
  61. GRB 050730: early TAROT optical observations
  62. Swift/UVOT photometry of GRB050730
  63. GRB050730: Refined BAT analysis of the Swift-BAT burst
  64. GRB 050730: Swift XRT afterglow observations
  65. GRB 050730 XMM-Newton observation
  66. GRB050730, afterglow observations
  67. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  68. GRB050730: Liverpool Telescope optical observations
  69. GRB 050730, optical candidate
  70. GRB050730: Swift-BAT detection of a weak burst
  71. GRB 050713A: Swift XRT extended light curve
  72. GRB050726: Swift UVOT observations
  73. GRB 050724: Chandra Observations of the X-ray Afterglow
  74. GRB050713: analysis of the XMM-Newton observation
  75. Swift-BAT trigger 147918 is not a real GRB
  76. GRB 050727: RTT150 optical observations
  77. GRB050727: KAIT optical limit
  78. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  79. GRB 050726: early Swift XRT analysis results
  80. GRB050726: Swift-BAT detection of a weak burst
  81. GRB 050724: SWIFT XRT refined position
  82. GRB 050724: optical and near-IR observations
  83. GRB 050724: Swift/UVOT Upper Limit
  84. GRB 050724: early Swift XRT analysis results
  85. GRB050724: Refined analysis of the Swift-BAT possible short burst
  86. GRB050724: a short-burst detected by Swift
  87. Swift-BAT trigger 147325 is not due to a real GRB
  88. GRB050723: XRT distributed coordinates are not related to the burst
  89. GRB 050721A: Swift-BAT refined analysis
  90. GRB 050721A: Early Swift XRT analysis results
  91. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  92. GRB 050721a: Optical Observations
  93. GRB050721A: Swift-BAT detection of a weak burst
  94. GRB 050714a: Refined XRT analysis and afterglow confirmation
  95. Swift-BAT trigger 146731 is not a real GRB
  96. Swift-BAT detection of a possible GRB
  97. GRB050717
  98. Konus-Wind observation of GRB 050717
  99. Swift/UVOT Observations of GRB 050717
  100. GRB 050717: Swift-BAT refined analysis

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