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Session 101 - The Sun.
Display session, Thursday, January 18
North Banquet Hall, Convention Center

[101.11] Probing the Sun's Interior Structure and Flows By Tomographic Inversion

A. G. Kosovichev (Stanford U)

I present results of inversion of travel-time maps recently obtained by Duvall, Jefferies and Harvey (1995, BAAS, v.25, 950). The maps represent measurements of the time for acoustic waves to travel between points on a solar surface and surrounding annuli. The measurements are sensitive to perturbations of the sound speed and flows along the ray pathes. A 3D inversion method based on Fermat's Principle and a conjugate-gradient technique has been applied to infer the sound speed and the velocity of flows from the observations obtained by Duvall et al. at the South Pole Jan. 4-5 1991. The spatial resolution of the inversion is 1.75 degree in both longitude and latitude, and 15 Mm in depth. The results reveal large-scale subsurface structures and flows related to the active regions, and are important for understanding the physics of solar activity and large-scale convection.

Program listing for Thursday