Time-Distance Inversions and Kernels for Ring Diagrams

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Time-Distance Inversions and Kernels for Ring
Diagrams

• Aaron Birch

• Outline
• TD Inversions
• Kernels for Ring Diagrams

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Motivation
Also holography inversions
Kosovichev, Zhao et al.
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Zhao et al., 2001, test inversions
Also Giles comparison with normal- mode inversions
Couvidat et al., compare ray and Born
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From S. Korzennik, test inversions
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From S. Korzennik, test inversions
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Future Work for TD Inversions

• Kernels
• Greens functions exact vs. normal modes
• Dependence on source/damping models ?
• Regularization
• How much what kind of averaging ?
• Magnetic Fields ?
• How well does treating B as c work ?

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B. Kernels for Ring-Diagrams

• Want
• Two steps
• Linear sensitivity of U parameters to power
• Linear sensitivity of power to local flows

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Example Ring Kernel, l300,n4
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Blue slice through kernel Black 1d undamped
model
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Future Work for/with Ring Kernels

• Inversions of ring data
• Joint inversion of time-distance, holography,
  direct modeling, and ring data, have uniform
  theoretical treatment
• Model systematic effects (e.g. line of sight,
  Postel remapping) ?

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