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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').

10636 results found.

  1. GRB051028:MASTER correction and final results
  2. GRB 051022: RTT150 optical observations
  3. GRB051028: Swift/UVOT upper limits
  4. GRB051028: Swift XRT Position
  5. GRB051022: Swift XRT measurement of jet break
  6. SGR 1806-20: continued moderate activity seen with INTEGRAL
  7. Chandra Observations of GRB 051022
  8. GRB 051022 Chandra Observations scheduled
  9. Konus-Wind observation of GRB 051022
  10. GRB 051022 (=H3950): SXC Flight Localization is Valid
  11. GRB 051021B: Refined analysis of the Swift-BAT burst
  12. GRB 051022A: ROTSE-III Optical Limits
  13. GRB 050502b: Optical limit
  14. GRB 051016B: refined analysis of the Swift/XRT data
  15. GRB 051016: LCO optical and near-IR imaging
  16. GRB050805A: Rc optical observations
  17. GRB 051008 - a low redshift low-luminosity burst?
  18. Konus-Wind observation of GRB 051008
  19. GRB 051008, optical observations
  20. GRB 051006: P60 Observations
  21. GRB 051006: XRT refined analysis
  22. GRB051006: Refined analysis of the Swift-BAT burst
  23. GRB 051006: XRT position
  24. GRB051006: Swift detection of a burst
  25. GRB 051001: Swift XRT refined analysis
  26. GRB 051001: AAT infra-red observations
  27. GRB 051001: ROTSE-III Optical Limits
  28. GRB050922C: optical observation
  29. GRB050922C: UVES/VLT high resolution spectroscopy
  30. GRB050925: Swift/XRT limits
  31. GRB/SGR 050925: IR Observations
  32. GRB050925: Swift-BAT detection of a short burst
  33. GRB 050922B: Correction to BAT refined analysis, longer burst
  34. Konus-Wind observation of GRB 050922C
  35. GRB050922C: Optical Observations
  36. GRB 050922C: Swift XRT refined analysis
  37. GRB 050922C: optical obserations
  38. GRB 050922C: ROTSE-IIId Refined Analysis
  39. GRB 050922B: ROTSE-III Optical Limits
  40. Possible GRB 050922 detected by INTEGRAL
  41. GRB050820B: analysis of the XMM-Newton observation
  42. GRB050916: Swift/UVOT Upper Limits
  43. GRB 050918 - A long GRB detected by INTEGRAL
  44. Swift-BAT trigger 155535 is definitely not a GRB
  45. GRB 050916: XRT position
  46. GRB050916: Swift-BAT detection of a long weak burst
  47. GRB 050915B: XRT position
  48. GRB050915B: Swift-BAT detection of a long bright burst
  49. GRB 050915: Swift-BAT refined analysis
  50. GRB050915: P60 Optical Observations
  51. GRB 050915: ROTSE-III optical limits
  52. Swift is in normal operation
  53. GRB 050911: Swift-BAT refined analysis
  54. GRB 050911: z~0.16 cluster in the field
  55. GRB050911: Swift-BAT detection of a long burst
  56. GRB 050910a: TAROT early optical limits
  57. GRB 050906: Possible X-ray Counterpart
  58. GRB 050908: Swift-BAT refined analysis
  59. GRB 050908: Optical observations
  60. GRB 050908: Prompt PROMPT Observations
  61. Swift trigger 154073 is not a GRB
  62. GRB050904: CrAO optical observations
  63. GRB 050906: Swift-BAT refined analysis
  64. GRB 050906: Radio Observations
  65. GRB 050906: Bright galaxy in BAT error box
  66. GRB 050904: Swift/UVOT observations
  67. GRB 050904: early Swift XRT analysis results
  68. GRB 050827: P200 NIR Observations
  69. GRB050824, HETE-2 Observation
  70. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  71. GRB050824, I-band imaging
  72. GRB 050822: refined XRT analysis
  73. GRB 050824: XRT refined analysis and possible afterglow detection
  74. GRB 050824: ROTSE-III Optical Limits
  75. GRB050820A: RTT150 optical observations
  76. GRB 050822: Swift-BAT refined analysis
  77. GRB050820A: RTT150 optical observations
  78. GRB 050820a - corrections to GCN 3846
  79. GRB 050822: ROTSE-III Prompt Optical Limits
  80. GRB050820B: BAT-Swift detection of a bright GRB
  81. GRB 050820: High Resolution Spectroscopy from Keck
  82. GRB 050820: Swift detection of a GRB
  83. Swift-BAT trigger 150993 is not a GRB
  84. GRB 050815: ROTSE-III Optical Limits
  85. GRB050814: Fading red source
  86. GRB050814: P60 Optical Afterglow Candidate
  87. GRB 050814: XRT refined analysis
  88. GRB050814: Refined analysis of the Swift-BAT burst
  89. GRB 050814: Swift XRT Afterglow Localization
  90. GRB050813: RTT150 optical observations
  91. GRB 050813: KAIT optical limit
  92. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  93. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  94. Detection of an intermediate burst from SGR 1806-20 on August 8
  95. GRB 050807: ROTSE-III Optical Limits
  96. GRB050803, optical observations
  97. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  98. GRB 050803: RTT150 optical observations
  99. GRB050803: CrAO optical observations, possible OT candidate
  100. GRB 050803: Swift-BAT refined analysis

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