On magnetoacoustic-gravity-inertial (MAGI) waves - I. Generation, propagation, dissipation and radiation

Abstract

The general equations of fluid mechanics under gravity, rotation and external magnetic fields are used to study the generation, propagation and radiation of magnetoacoustic-gravity-inertial (MAGI) waves, coupling the four restoring forces: pressure, gravity, magnetic field and Coriolis-centrifugal forces. The mean state is assumed to be an ionized rotating atmosphere, and the elimination among the linear, non-dissipative perturbations leads to a matrix MAGI wave operator applying to the velocity perturbation vector, which describes acoustic, magnetic, internal and inertial waves and all their couplings. The non-linear and viscous, thermal and resistive dissipative terms are retained, to model the sources of MAGI waves, which consist of hydrodynamic, hydromagnetic, hydrogravity and hydrorotation tensors, representing MAGI wave generation by (i) stratified hydromagnetic turbulence; (ii) ionized fluid inhomogeneities and (iii) heat dissipation by fluid viscosity and electrical resistance. The energy flux of MAGI wave sources is used in Part II to estimate the radiative losses of the Sun, and the luminosities of a variety of stars, including magnetic and non-magnetic and rotating and non-rotating, supporting the idea that energy (and mass) transport in stellar atmospheres is due to MAGI waves. © 2010 The Author. Journal compilation © 2010 RAS.