An Isaac Newton Institute Workshop

MAGNETOHYDRODYNAMICS OF STELLAR INTERIORS <br> Supported by the European Commission, Sixth Framework Programme - <br> Marie Curie Conferences and Training Courses - MSCF-CT-2003-503674

Forward Modeling for Local Helioseismology

Author: A.C. Birch (Colorado Resarch Associates Division, NorthWest Research Associates, Inc.)


In order to interpret measurements made with local helioseismology it is crucial to understand the sensitivity of these measurements to different types of perturbations to a solar model. Local helioseismic measurements are sensitive not only to subsurface mass flows, sound-speed variations, and magnetic field, but also to local changes in the wave damping and excitation rates. I will show example calculations of the sensitivity of travel-times measured by time-distance helioseismology and phase shifts measured by acoustic holography to flows, sound speed perturbations, and local changes in the wave excitation and damping rates.