发表机构
University of California Los Angeles; Osaka University; California Institute of Technology; SETI Institute; University of Hawai‘i; Flatiron Institute; Indiana University（加州大学洛杉矶分校; 大阪大学; 加州理工学院; SETI研究所; 夏威夷大学; 平顿研究所; 印第安纳大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用KPF光谱仪数据，发现以恒星振荡频率ν_max预测F/G/K矮星宏观湍流，比传统温度法精度高4倍，RMS达90 m/s，揭示了其与对流运动的深层关联。
AI 中文摘要
我们利用凯克行星探测器（KPF）光谱仪的高分辨率和光谱稳定性，通过恒星交叉相关函数（CCF）研究宏观湍流展宽。作为校准样本，我们使用主序基准慢自转体，其v$\sin$i < 4 km/s，这些恒星的自转速率源自最稳健的星震学模式分裂测量，与谱线展宽无关。我们拟合了宏观湍流与推导出的$\nu_{max}$（恒星振荡最大功率频率）之间的线性关系，其RMS离散度为90 m/s。以往研究针对T$_{eff}$校准宏观湍流，但我们发现$\nu_{max}$作为预测因子的离散度低4倍，表明$\nu_{max}$与对流运动之间存在更深层次的联系。
英文摘要
We leverage the high resolution and spectral stability of the Keck Planet Finder (KPF) spectrograph to investigate macroturbulence broadening via the stellar cross-correlation function (CCF). As our calibration sample, we use main sequence benchmark slow-rotators v$\sin$i < 4 km/s where rotation rates were derived from the most robust asteroseismic mode splitting measurements, independent from spectral line broadening. We fit a linear relationship for macroturbulence as a function of derived $ν_{max}$, the frequency of maximum power due to stellar oscillations, with an RMS scatter of 90 m/s. Previous studies have calibrated macroturbulence against T$_{eff}$, but we find $ν_{max}$ to be a lower dispersion predictor by a factor of 4 indicating a deeper relationship between $ν_{max}$and convective motions.
CommentsSubmitted for review to AJ
