Stability of radial and non-radial pulsation modes of massive ZAMS models C

Abstract

We have computed non-adiabatic eigenvalues for radial and non-radial pulsation modes of star models between 80 and 120 Me with composition of X=0.70 and Z=0.02. The radial fundamental mode is unstable in models with mass greater than 95 Mp , but the first overtone mode is always stable. The non-radial modes are all stable for all models, but the Y_=2 f-mode is the closest to being driven. The non-radial modes are progressively more stable with higher e and with higher n (for both p- and g-modes). Thus, our results indicate that radial pulsation limits the upper mass of a star.