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Appendix A: Harmonic highest degree k_c

	Fig. A.1 Rank of the highest harmonic degree kc as a function of E (with K = 10-4) and K (with E = 10-4) for different values of A (in logarithmic scales). Left: kc − E. Right: kc − K.
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The expression of the highest harmonic degree, given in Eq. (108), is plotted as a function of the Ekman number and of the thermal diffusivity for various regimes from A ≪ 1 to A ≫ 1. It corresponds to the upper bound of harmonic degree, which is sufficient to represent all the resonances of the spectrum.

Appendix B: Relative differences η_l and η_H

The results provided by analytical expressions of Eqs. (65) and (71) have been compared to those given by the complete formula of the energy dissipated by viscous friction (Eq. (38)). The colour maps of Fig. B.1 correspond to the computation of the width at mid-height l₁₁ and height of the main resonance, which are summarized in Fig. 8. The relative differences η_l and η_H are calculated using the expressions (B.1)l_ana and coming from Eqs. (65) and (71), and l_th and being computed with Eq. (38). The plots highlight the asymptotic domains, in dark blue, where the analytical formulae constitute a relevant approximation for the width and height of a resonance, and the critical transition zones where they cannot be applied. The light blue horizontal line corresponds to A ~ A₁₁, the hyper-resonant case. The colour gradient in the regions near E ~ 10^-2 and K ~ 10^-2 indicates the values of A, E, and K for which the condition of the quasi-adiabatic approximation (Eq. (85)) is not satisfied. The same can be done with the energy dissipated by thermal diffusion.

	Fig. B.1 ηl and ηH as a function of A, E, and K in logarithm scales. White contours highlight critical zones where the quasi-adiabatic assumption () or the asymptotic condition (A ≠ A11) are not satisfied. Top left: ηl−(E,A). Top right: ηl−(K,A). Bottom left: ηH−(E,A). Bottom right: ηH−(K,A).
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© ESO, 2015