Sources of uncertainty in direct seismological measurements of the solar helium abundance
Sources of uncertainty in direct seismological measurements of the solar helium abundance
复制标题
太阳氦丰度直接地震测量的不确定性来源
DOI：
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发表时间：
1992
期刊：
影响因子：
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通讯作者：
Michael Thompson
中科院分区：
文献类型：
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作者：
A. Kosovichev;J. Christensen;W. Daeppen;W. Dziembowski;D. Gough;Michael Thompson
本文比较了Dappen等（1988，1990，1991）和Dziembowski等（1990，1991，1992）最近对太阳对流区氦丰度的不一致估计方法。本文报告的调查的目的是确定差异的主要来源。使用作为代理数据本征频率的一组模式的理论太阳能模型，计算与相同的物理是一个参考模型的频率与这些数据进行比较，这两种方法产生类似的结果。因此，我们确定的差异的主要来源是不是在反演本身，这基本上产生一个衡量的变化的绝热指数γ的材料在He II电离区。相反，它是在状态方程中处理重元素时采用的近似值，用于将伽马的变化与化学成分联系起来。我们得到可以接受的一致的结果时，反演太阳能数据的两种方法使用相同的状态方程。我们试图确定可能的不确定性的剩余来源。
The methods by which Dappen et al. (1988, 1990, 1991) and Dziembowski et al. (1990, 1991, 1992) recently obtained discrepant estimates of the helium abundance in the solar convection zone are compared. The aim of the investigation reported in this paper is to identify the main source of the discrepancy. Using as proxy data eigenfrequencies of a set of modes of a theoretical solar model, computed with the same physics as were the frequencies of a reference model with which these data are compared, the two methods yield similar results. Thus we ascertain that the principal source of the discrepancy is not in the inversions themselves, which yield essentially a measure of the variation of the adiabatic exponent gamma of the material in the He II ionization zone. Instead it is in the approximations adopted in the treatment of heavy elements in the equation of state used to relate the variation of gamma to chemical composition. We obtain acceptably consistent results when inverting solar data by two methods using the same equation of state. We attempt to identify the likely residual sources of uncertainty.