论文标题
白矮人质量 - 拉迪乌斯关系的重力红移测量
A Gravitational Redshift Measurement of the White Dwarf Mass-Radius Relation
论文作者
论文摘要
白矮人的质量 - 拉迪乌斯关系在很大程度上取决于退化电子状态的方程，这会导致恒星半径随着质量的增加而减小。在这里，我们使用重力红移效应从观察到这种关系，这是对恒星质量和半径之间比率的一般相对性的预测。利用Sloan数字天空调查和Gaia空间观测站的三千多名白矮星的观察，我们从吸收系线中得出了明显的径向速度，来自光度法和视差的恒星半径，以及通过将大气模型拟合的表面重力。通过平均具有相似半径和独立的表面重力的白色矮人的明显径向速度，我们取消了随机的多普勒移位并测量潜在的重力红移。使用这些结果，我们从经验上测量了各种恒星质量的白矮人质量 - 拉迪乌斯关系。我们的结果与领先的理论模型一致，我们的方法可以与未来的观察结果一起使用，以限制白矮人的核心组成和进化。
The mass-radius relation of white dwarfs is largely determined by the equation of state of degenerate electrons, which causes the stellar radius to decrease as mass increases. Here we observationally measure this relation using the gravitational redshift effect, a prediction of general relativity that depends on the ratio between stellar mass and radius. Using observations of over three thousand white dwarfs from the Sloan Digital Sky Survey and the Gaia space observatory, we derive apparent radial velocities from absorption lines, stellar radii from photometry and parallaxes, and surface gravities by fitting atmospheric models to spectra. By averaging the apparent radial velocities of white dwarfs with similar radii and, independently, surface gravities, we cancel out random Doppler shifts and measure the underlying gravitational redshift. Using these results, we empirically measure the white dwarf mass-radius relation across a wide range of stellar masses. Our results are consistent with leading theoretical models, and our methods could be used with future observations to empirically constrain white dwarf core composition and evolution.
