本文通过扩展的改进多参数指数型(the extended improved multiparameter exponential-type,EIMPET)势能模型,结合实验光谱数据,研究了H_(2)和HD分子的热力学性质.首先利用解析势能曲线计算得到分子的振转能级,其次结合量子统计系综理...本文通过扩展的改进多参数指数型(the extended improved multiparameter exponential-type,EIMPET)势能模型,结合实验光谱数据,研究了H_(2)和HD分子的热力学性质.首先利用解析势能曲线计算得到分子的振转能级,其次结合量子统计系综理论计算了分子在100—6000 K温度下的配分函数、摩尔热容、摩尔熵、摩尔焓以及约化摩尔吉布斯自由能.计算结果与美国国家标准与技术研究所(National Institute of Standards and Technology,NIST)数据库中的数据具有良好的一致性.本文的理论方法可用于预测某些气态物质的热力学性质.展开更多
Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects...Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects of magnetic activity on frequency shifts, we calculate frequency shifts for the radial and l=1 p-modes of HD 49933 with the general variational method, which evaluates the shifts using a spa- tial integral of the product of a kernel and some sources. The theoretical frequency shifts reproduce the observation well. The magnitudes and positions of the sources are determined according to a χ2 criterion. We predict the source that contributes to both the l = 0 and l= 1 modes is located 0.48 - 0.62 Mm below the surface of the star. In addition, based on the assumption that A0 is proportional to the change in the MglI activity index △iMgⅡ, we obtain that the change in MgⅡ index between the minimum and maximum of the cycle during the period of HD 49933 is about 0.665. The magnitude of the frequency shifts compared to the Sun already demonstrates that HD 49933 is much more active than the Sun, which is further confirmed in this pa- per. Furthermore, our calculation of the frequency shifts for l = 1 modes indicates the variation of turbulent velocity in the stellar convective zone may be an important source for the l = 1 shifts.展开更多
文摘本文通过扩展的改进多参数指数型(the extended improved multiparameter exponential-type,EIMPET)势能模型,结合实验光谱数据,研究了H_(2)和HD分子的热力学性质.首先利用解析势能曲线计算得到分子的振转能级,其次结合量子统计系综理论计算了分子在100—6000 K温度下的配分函数、摩尔热容、摩尔熵、摩尔焓以及约化摩尔吉布斯自由能.计算结果与美国国家标准与技术研究所(National Institute of Standards and Technology,NIST)数据库中的数据具有良好的一致性.本文的理论方法可用于预测某些气态物质的热力学性质.
基金Supported by the National Natural Science Foundation of China
文摘Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects of magnetic activity on frequency shifts, we calculate frequency shifts for the radial and l=1 p-modes of HD 49933 with the general variational method, which evaluates the shifts using a spa- tial integral of the product of a kernel and some sources. The theoretical frequency shifts reproduce the observation well. The magnitudes and positions of the sources are determined according to a χ2 criterion. We predict the source that contributes to both the l = 0 and l= 1 modes is located 0.48 - 0.62 Mm below the surface of the star. In addition, based on the assumption that A0 is proportional to the change in the MglI activity index △iMgⅡ, we obtain that the change in MgⅡ index between the minimum and maximum of the cycle during the period of HD 49933 is about 0.665. The magnitude of the frequency shifts compared to the Sun already demonstrates that HD 49933 is much more active than the Sun, which is further confirmed in this pa- per. Furthermore, our calculation of the frequency shifts for l = 1 modes indicates the variation of turbulent velocity in the stellar convective zone may be an important source for the l = 1 shifts.
