对低温变星的脉动激发机制中的一些争议问题进行了评述:(1)大多数人相信γDoradus型变星是由所谓的阻塞对流机制所激发.研究表明,γ Doradus和δScuti变星的激发机制不存在任何实质性的差别,他们是更大一类δ Scuti-γ Doradus变星的2个次群:δScuti变星是p模脉动子群;而γ Doradus是g模脉动子群.(2)大多数人相信太阳5分钟振荡和恒星的类太阳振荡被对流所阻尼,他们是由所谓湍流随机激发机制驱动的.研究表明,对流并非单纯只是脉动的阻尼机制,否则无法解释Mira变星和类Mira变星.利用非局部和非定常的恒星对流理论,不仅可以重现δ Scuti和γ Doradus脉动不稳定区,也可重现低光度红巨星的类太阳振荡和高光度红巨星的类Mira振荡特性.%The controversies about the excitation mechanism for cool variables are reviewed:(1) Most people believe that γ Doradus stars are excited by so called convec tive blocking.Our researches show that the excitation of γ Doradus has no difference from that of δ Scuti.They are two subgroups of a broader type of δ Stuti-γ Doradus stars:δ Scuti is the p-mode subgroup,while γ Doradus is the g-mode subgroup.(2) Most people believe that the Solar-and Solar-like oscillations of stars are damped by convection,and they are excited by so called stochastic effects of turbulence.Our researches show that convection is not solely a damping mechanism for stellar oscillations,otherwise it is not able to explain the excitation of Mira and Mira-like stars.It can be repeated not only the δ Scuti and γ Doradus strip,but also the characteristics of Solar-like and Mira-like oscillations,respectively,for the low-and high-luminosity red stars by using our non-local and time-dependent theory of convection.
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