M33 WR and Of-type Stars

Massive star evolutionary models generally predict the correct ratio of WC-type and WN-type Wolf-Rayet stars at low metallicities, but underestimate the ratio at higher (solar...大质量恒星演化模型通常可在低金属丰度（metallicity）条件下，准确预测WC型（WC-type）与WN型（WN-type）沃尔夫-拉叶星（Wolf-Rayet stars）的数量比值，但在高于（太阳……）的金属丰度环境中，该模型会低估这一比值。