We investigate the pulsational stability of massive ( M \gtrsim 120 M _ { \odot } ) main sequence stars of a range of metallicities , including primordial , Population III stars .
We include a formulation of convective damping motivated by numerical simulations of the interaction between convection and periodic shear flows .
We find that convective viscosity is likely strong enough to stabilize radial pulsations whenever nuclear-burning ( the \epsilon -mechanism ) is the dominant source of driving .
This suggests that massive main sequence stars with Z \lesssim 2 \times 10 ^ { -3 } are pulsationally stable and are unlikely to experience pulsation-driven mass loss on the main sequence .
These conclusions are , however , sensitive to the form of the convective viscosity and highlight the need for further high-resolution simulations of the convection-oscillation interaction .
For more metal-rich stars ( Z \gtrsim 2 \times 10 ^ { -3 } ) , the dominant pulsational driving arises due to the \kappa -mechanism arising from the iron-bump in opacity and is strong enough to overcome convective damping .
Our results highlight that even for oscillations with periods a few orders of magnitude shorter than the outer convective turnover time , the “ frozen-in ” approximation for the convection-oscillation interaction is inappropriate , and convective damping should be taken into account when assessing mode stability .