THE RESOLVING POWER OF CURRENT HELIOSEISMIC INVERSIONS FOR THE SUNS INTERNAL-ROTATION

The inferred internal solar rotation rate obtained from helioseismic inversion is a nonlocal average of the true rotation rate; hence some care is required in the interpretation of the results of such inversions. We present kernels which describe the weighting of the average, for an inversion that is representative of recent work. Of particular interest is the fact that the so-called polar rate is actually an extrapolation from lower latitudes: the current helioseismic data do not permit us to construct a solution whose averaging kernel is localized at high solar latitude. Nonetheless, our results do not change the basic conclusion that the average radial gradient of the rotation rate in the solar convection zone is small. Finally, we demonstrate that more localized measures of the solar rotation are possible with the more complete data that should become available from new helioseismology projects.