Stellar radius response exponent
= Stellar radius response exponent
{title2=$\zeta=d\log R/d\log M$}
The <stellar radius response exponent> measures how a <star>'s <radius> changes as it loses <mass>. The adiabatic exponent $\zeta_{\rm ad}$ describes loss too rapid for thermal adjustment; the equilibrium exponent $\zeta_{\rm eq}$ follows a sequence of thermally relaxed <stars>. Compare $\zeta_{\rm ad}$ with the <Roche-lobe radius response exponent> to test dynamical stability.