Axion mechanism of Sun luminosity: light shining through the solar radiation zone

It is shown that the hypothesis of the axion mechanism of Sun luminosity suggesting that the solar axion particles are born in the core of the Sun and may be efficiently converted back into $\gamma$-quanta in the magnetic field of the solar overshoot tachocline is physically relevant. As a result, it is also shown that the intensity variations of the $\gamma$-quanta of axion origin, induced by the magnetic field variations in the tachocline, directly cause the Sun luminosity %and total solar irradiance (TSI) variations and eventually characterize the active and quiet states of the Sun. Within the framework of this mechanism estimations of the strength of the axion coupling to a photon ($g_{a \gamma} = 3.6 \cdot 10^{-11} GeV^{-1}$) and the hadronic axion particle mass ($m_a \sim 2.3 \cdot 10^{-2} eV$) have been obtained. It is also shown that the claimed axion parameters do not contradict any known experimental and theoretical model-independent limitations.