论文标题
一种基于Hermite-Gaussian的径向速度估计方法
A Hermite-Gaussian Based Radial Velocity Estimation Method
论文作者
论文摘要
作为一种用于检测轨道遥远恒星的系型系的成功技术，径向速度方法旨在检测恒星光谱中的周期性多普勒移位。我们引入了一种新的，数学上严格的方法来检测这种信号，以说明相邻波长的功能关系，最大程度地减少波长插值的作用，说明异性噪声噪声，并且很容易允许统计推断。使用Hermite-Gaussian函数，我们表明在许多情况下，可以将检测到频谱中多普勒移位的问题减少为线性回归。一项模拟研究表明，所提出的方法能够准确估计单个光谱的径向速度，精度低于0.3 m/s。此外，新方法通过将均方根误差降低到15 cm/s来优于传统的互相关函数方法。该方法还可以在从极端精确光谱仪（Expres）的一组新观测值中证明，并成功恢复了与以前对该行星系统的研究非常吻合的估计值。与此工作关联的数据和Python3代码可以在https://github.com/parkerholzer/hgrv_method上找到。该方法还在开源R软件包RVMethod中实现。
As the first successful technique used to detect exoplanets orbiting distant stars, the Radial Velocity Method aims to detect a periodic Doppler shift in a star's spectrum. We introduce a new, mathematically rigorous, approach to detect such a signal that accounts for functional relationships of neighboring wavelengths, minimizes the role of wavelength interpolation, accounts for heteroskedastic noise, and easily allows for statistical inference. Using Hermite-Gaussian functions, we show that the problem of detecting a Doppler shift in the spectrum can be reduced to linear regression in many settings. A simulation study demonstrates that the proposed method is able to accurately estimate an individual spectrum's radial velocity with precision below 0.3 m/s. Furthermore, the new method outperforms the traditional Cross-Correlation Function approach by reducing the root mean squared error up to 15 cm/s. The proposed method is also demonstrated on a new set of observations from the EXtreme PREcision Spectrometer (EXPRES) for the star 51 Pegasi, and successfully recovers estimates that agree well with previous studies of this planetary system. Data and Python3 code associated with this work can be found at https://github.com/parkerholzer/hgrv_method. The method is also implemented in the open source R package rvmethod.
