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Basic quantities in stellar photographic photometry (in particular, colour index and "effective wavelength") are formulated according to the assumptions that: 1) stellar radiation may be represented by some black body equivalent and 2) within the limits of a single photometric "receiver", intensity-wavelength relationship of the radiation may be taken as linear. Foundations and applicability of these assumptions are examined. On the basis of this the photometric side of the problems of space reddening... Basic quantities in stellar photographic photometry (in particular, colour index and "effective wavelength") are formulated according to the assumptions that: 1) stellar radiation may be represented by some black body equivalent and 2) within the limits of a single photometric "receiver", intensity-wavelength relationship of the radiation may be taken as linear. Foundations and applicability of these assumptions are examined. On the basis of this the photometric side of the problems of space reddening etc. are discussed. We considered in detail the use of effective wavelength by objective grating method in stellar photometry and have shown that with suitable photometric technique and right choice of grating it is possible to obtain in two colour photometry (say, ultraviolet and photovisual) the results with same degree of accuracy as might be obtained in three colour arrangement. 本文對着當前的發展,綜述了照相方法在恆星光度学中的地位.接着用兩個簡單的假设,即星体幅射的黑體近似和累積亮度範圍中的直线近似,把恆星光度学中的基本定義(如有效波長、等光波長和色指数等)和主要问题(如空間红化,亮度效应等)表以公式.在进行的時候,我们详细地讨论了這兩个假设的依據. 我們提出了在兩色光度学中物端光栅所能接觸到的问题,着重地敘述了空间吸收和光度型的辨認,並且把应用这种方法的先決條件,它的優點和它所受到的限制加以讨论. It has been shown by S. A. Zhevakin that the critical double ionizarion zone of helium Hell in the envelope of a pulsating star, such as RR Lyrae, is a mechanism giving rise to the auto-oscillation of the star. The mass of the star should have such a value that its Hell zone has a definite non-adiabatic degree of oscillation, so as to excite its auto-oscillation. In the present paper the mass of RR Lyrae is determined on the basis of Zhevakin's theory of stellar variability.The mass of RR Lyrae is first... It has been shown by S. A. Zhevakin that the critical double ionizarion zone of helium Hell in the envelope of a pulsating star, such as RR Lyrae, is a mechanism giving rise to the auto-oscillation of the star. The mass of the star should have such a value that its Hell zone has a definite non-adiabatic degree of oscillation, so as to excite its auto-oscillation. In the present paper the mass of RR Lyrae is determined on the basis of Zhevakin's theory of stellar variability.The mass of RR Lyrae is first assumed to have Sandage's value 1.15 M⊙. Accurate calculations of various physical quantities in the envelope of RR Lyrae are made. The non-adiabatic degree of oscillation in the Hell zone is found to be y = 3.16, which is not admissible by Zhevakin's theory of stellar variability, so that the mass M of RR Lyrae cannot be 1.15M⊙.In order to estimate the mass of RR Lyrae, we use a relation between y and M, given by Zhevakin, based on the supposition that the stellar envelope is built on polytrope of index n. It is found for RR Lyrae that the polytropic index n is 2.818, so that the mass M lies between 0.47 M⊙ and 0.99 M⊙. On the other hand Oke and Bonsack concluded from the spectrum analysis of RR Lyrae and the period-density relation, that the mass M of RR Lyrae is substantially less than the solar mass M⊙. Based upon all these considerations we choose a possible value of M to be 0.85 M⊙ and make all the calculations anew. We find that y = 2.27 for M = 0.85 M⊙, which satisfies Zhevakin's condition (7.1). We hope that further observations will decide whether the mass M of RR Lyrae is really equal to 0.85 M⊙. 这是根据日瓦金的造父变星理论来间接确定造父变星质量的一个新方法.现用这方法求天琴座RR星的质量.按照这个理论,变星的质量必须对应于它的振动非绝热度.计算指出,桑德吉的结论,天琴座RR星的质量为1.15M不能成立.从日瓦金星体包层是多层球的近似理论及光谱分析方面的考虑,我们假定天琴座RR星的质量为0.85M.从这个数值计算出的振动非绝热度同日瓦金理论中对造父变星的条件相符合.这证明0.85M的值是该变星质量的可能值.至于这是否真正代表该星的质量,尚待进一步天文观测的证实. In the first introductory part it is pointed out that the main difference among current theories of stellar evolution is in the evolutionary stage after stars move onto the main sequence.Three kinds of theory are mentioned.The first is the theory of stellar evolution with constant mass,the second is the corpuscular emission theory of stellar evolution,and the third is the theory of direct evolution of main sequence stars to white dwarfs.The second part introduces the first theory.The difficulty... In the first introductory part it is pointed out that the main difference among current theories of stellar evolution is in the evolutionary stage after stars move onto the main sequence.Three kinds of theory are mentioned.The first is the theory of stellar evolution with constant mass,the second is the corpuscular emission theory of stellar evolution,and the third is the theory of direct evolution of main sequence stars to white dwarfs.The second part introduces the first theory.The difficulty of this theory,as is well known,is how to effect the evolution to white dwarfs of the main sequence stars after they have evolved to red giants and/or supergiants.Observational evidence is scanty,and,above all,theoretically,it is blank. In the third part,the second theory is stated.This theory,as we point out,should contain the following assumption:either it denies the existence of the initial luminosity function of main sequence stars,or it requires the relation 0 (μ_0) between the initial mass of a star0,and its initial mean molecular weight,μ_0,exactly the same as the relation(μ) between the mass of the staand its mean molecular weight,μ, after the evolution by corpuscular emission.Neither of these two is likely possible. Moreover,the essential data,derived from investigation of stellar structure,on which this theory is based is not reliable as compared to the current ones,obtained by much more careful considerations in the same field of investigation.Hence this theory is not trustworthy. The fourth part relates about the third theory.It is pointed out that the key point of this theory is whether a main sequence star will evolve with its chemical composition homogeneous throughout the whole star and thus shift to the left of the main sequence so as finally to be able to evolve to a white dwarf. 在第一部分引言中,说明现代恒星演化学说的分歧主要是在恒星形成主序星以后的演化.本文叙述三种学说:第一种是质量固定的恒星演化学说,第二种是微粒发射的恒星演化学说,第三种是主序星径向白矮星的演化学说.第二部分介绍第一种学说,指出困难之点在恒星脱离主星序演变成红巨星、超巨星后,怎样演化到白矮星的问题,观测资料既贫乏,理论方面更是空白.第三部分介绍第二种学说,指出这学说蕴含着下面的假定:或是否认主序星原始光度函数的存在,或是要求主序星的原始质量 m_0和原始平均分子量μ_0的关系 m_0(μ_0)恰好是因微粒发射后所演变成的质量 m 和平均分子量μ的关系 m(μ).这两者都是很少可能的.而这学说所根据从内部结构理论得到的主要数据,就近几年来好些同类研究,用较精密方法所得的计算结果来说,显然是不正确的.所以这学说的可靠性是很小的.第四部分介绍第三种学说,指出这学说的主要关键在一般的主序星能否因自转而使恒星的化学成份保持为内外均匀的星型,从而在赫-罗图上自主序星向左演变,演化为白矮星.
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