Excitation of transverse magnetic tube waves in stellar convection zones

III. Effects of metallicity on wave energy spectra and fluxes

¹ Department of Physics, University of Texas at Arlington, Arlington, TX 76019, USA
² Institut für Theoretische Astrophysik der Universität Heidelberg, Tiergartenstr. 15, 69121 Heidelberg, Germany

Corresponding author: P. Ulmschneider, ulm@ita.uni-heidelberg.de

Received: 24 July 2001
Accepted: 3 December 2001

Abstract

In the previous two papers of this series, we developed an analytical method describing the generation of transverse tube waves in stellar convection zones and used it to compute the wave energy spectra and fluxes for late-type stars with the solar metal abundance (population I stars). We now extend these calculations to population II stars with effective temperatures ranging from  K to 10 000 K, gravities , and with three different metal abundances: 1/10, 1/100 and 1/1000 of solar metallicity. The obtained results are valid only for a single magnetic flux tube and they show that the effects of metallicity are important only for cool stars with  K and that the amount of the generated wave energy decreases roughly by an order of magnitude for every decrease of the metallicity by an order of magnitude. The maximum wave energy flux generated in population II stars is  erg cm^-2 s^-1 and it is practically the same for stars of different gravities and metallicities.