CoRA, NWRA, Inc. 7/18/2005 Time-Distance Inversions and Kernels for Ring Diagrams Aaron Birch Outline: A.TD Inversions B.Kernels for Ring Diagrams

CoRA, NWRA, Inc. 7/18/2005 Motivation Kosovichev, Zhao et al. Also holography inversions:

CoRA, NWRA, Inc. 7/18/2005 Couvidat et al., compare ray and Born Also Giles comparison with normal- mode inversions Zhao et al., 2001, test inversions

CoRA, NWRA, Inc. 7/18/2005 From S. Korzennik, test inversions

CoRA, NWRA, Inc. 7/18/2005 From S. Korzennik, test inversions

CoRA, NWRA, Inc. 7/18/2005 Future Work for TD Inversions Kernels –Green’s 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 ?

CoRA, NWRA, Inc. 7/18/2005 B. Kernels for Ring-Diagrams Want: Two steps: –Linear sensitivity of U parameters to power –Linear sensitivity of power to local flows

CoRA, NWRA, Inc. 7/18/2005 Example Ring Kernel, l=300,n=4

CoRA, NWRA, Inc. 7/18/2005 Blue: slice through kernel Black: 1d undamped model

CoRA, NWRA, Inc. 7/18/2005 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) ?

CoRA, NWRA, Inc. 7/18/2005