Near- and Far-Field Response to Compact Acoustic Sources in Stratified Convection Zones

Abstract

The role of the acoustic continuum associated with compact sources in the Sun's interior wave field is explored for a simple polytropic model. The continuum produces a near-field acoustic structure -- the so-called `acoustic jacket' -- that cannot be represented by a superposition of discrete normal modes. Particular attention is paid to monochromatic point sources of various frequency and depth, and to the surface velocity power that results, both in the discrete f- and p-mode spectrum and in the continuum. It is shown that a major effect of the continuum is to heal the surface wave field produced by compact sources, and therefore to hide them from view. It is found that the continuous spectrum is not a significant contributor to observable inter-ridge seismic power.

9 pages, 7 figures. To appear in in Astrophys. J. (accepted March 15 2013). Quicktime movies in Ancillary Material

References in corpus (1)

• Axisymmetric Scattering of p Modes by Thin Magnetic Tubes

Cited by in corpus (4)

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• An Analytical Approach to Scattering Between Two Thin Magnetic Flux Tubes in a Stratified Atmosphere
• Multiple Scattering of Seismic Waves from Ensembles of Upwardly Lossy Thin Flux Tubes