Title: Subphotospheric Dynamics of Flaring Active Regions

Author_list: Kosovichev, A.G., Duvall, T.L., Jr

Abstract: We present results of investigation of subsurface plasma
flows and emerging structures for several flaring active regions
(including AR 9393 and 10486). The results representing 3-D maps of
sound-speed perturbations and flow velocities are obtained from
SOHO/MDI full-disk Doppler data by time-distance helioseismology with
the horizontal resolution of 3 Mm, vertical resolution of 0.7-4 Mm (in
the depth range of 0-40 Mm), and temporal resolution of 8 hours.  These
maps are compared with the corresponding MDI magnetograms, and also
with coronal images to determine the role of subphotospheric dynamics
in the development of the active regions and their flaring activity.