论文标题
测量白色矮人表面上的精细结构常数； G191-B2B中Fe V吸收的详细分析
Measuring the fine structure constant on a white dwarf surface; a detailed analysis of Fe V absorption in G191-B2B
论文作者
论文摘要
在白色矮人G191-B2B表面的引力电位PHI = GM/RC^2比地球表面强的10,000倍。检测到许多光球吸收特征，使其成为测试基本常数依赖重力的理论的合适环境。我们已经在白色矮人表面测量了精细的结构常数，Alpha使用了G191-B2B的新校准的Hubble空间望远镜SPESTRUM，两套新的独立的实验室FE V波长集和新的原子计算，用于量化Fe V波长依赖性的灵敏度参数。获得的两个结果是：dalpha/alpha = 6.36 +/- [0.33（stat） + 1.94（sys）] x 10^{ - 5}和dalpha/alpha = 4.21 +/- [0.47（stat） + 2.35（sys） + 2.35（sys）] x 10^{ - 5}。测量表明，在存在强重力场的情况下，精细结构常数略有增加。总结了对系统错误的全面搜索，包括线路误差，线融合，白色矮人气氛的分层，二次Zeeman效应和电场效应，光电速度流，远距离波长扭曲的远距离扭曲以及在HST光谱中的远距离波长扭曲以及相对同位同位素的相对变化。没有完全解释观察到的偏差，但是系统的不确定性在实验室波长测量精度下在很大程度上受到了主导。
The gravitational potential phi = GM/Rc^2 at the surface of the white dwarf G191-B2B is 10,000 times stronger than that at the Earth's surface. Numerous photospheric absorption features are detected, making this a suitable environment to test theories in which the fundamental constants depend on gravity. We have measured the fine structure constant, alpha, at the white dwarf surface, used a newly calibrated Hubble Space Telescope STIS spectrum of G191-B2B, two new independent sets of laboratory Fe V wavelengths, and new atomic calculations of the sensitivity parameters that quantify Fe V wavelength dependency on alpha. The two results obtained are: dalpha/alpha = 6.36 +/- [0.33(stat) + 1.94(sys)] X 10^{-5} and dalpha/alpha = 4.21 +/- [0.47(stat) + 2.35(sys)] X 10^{-5}. The measurements hint that the fine structure constant increases slightly in the presence of strong gravitational fields. A comprehensive search for systematic errors is summarised, including possible effects from line misidentifications, line blending, stratification of the white dwarf atmosphere, the quadratic Zeeman effect and electric field effects, photospheric velocity flows, long-range wavelength distortions in the HST spectrum, and variations in the relative Fe isotopic abundances. None fully account for the observed deviation but the systematic uncertainties are heavily dominated by laboratory wavelength measurement precision.
