Propagating Linear Waves in Convectively Unstable Stellar Models: A Perturbative Approach

Authors. Papini, E.; Gizon, L.; Birch, A. C.

Journal. Solar Physics, Volume 289, Issue 6, pp.1919-1929

Abstract. Linear time-domain simulations of acoustic oscillations are unstable in the stellar convection zone. To overcome this problem it is customary to compute the oscillations of a stabilized background stellar model. The stabilization affects the result, however. Here we propose to use a perturbative approach (running the simulation twice) to approximately recover the acoustic wave field while preserving seismic reciprocity. To test the method we considered a 1D standard solar model. We found that the mode frequencies of the (unstable) standard solar model are well approximated by the perturbative approach within 1 μHz for low-degree modes with frequencies near 3 mHz. We also show that the perturbative approach is appropriate for correcting rotational-frequency kernels. Finally, we comment that the method can be generalized to wave propagation in 3D magnetized stellar interiors because the magnetic fields have stabilizing effects on convection.

Links. Solar Physics, NASA ADS, arXiv

Leave a Reply