The Epoch of Giant Planet Migration Planet Search Program. I. Near-Infrared Radial Velocity Jitter of Young Sun-like Stars
Quang H. Tran, Brendan P. Bowler, William D. Cochran, Michael Endl, Gudmundur Stefansson, Suvrath Mahadevan, Joe P. Ninan, Chad F. Bender, Samuel Halverson, Arp… 展开作者
Quang H. Tran, Brendan P. Bowler, William D. Cochran, Michael Endl, Gudmundur Stefansson, Suvrath Mahadevan, Joe P. Ninan, Chad F. Bender, Samuel Halverson, Arpita Roy, Ryan C. Terrien
我们目前的早期结果，从大行星迁移计划的时代，精确的RV调查超过100个中间年龄（$\sim$ 20 $-$ 200百万年）G和K矮星与可移动带行星光谱仪（HPF）在麦当劳天文台的霍比-埃伯利望远镜（HET）。该计划的目标是确定巨行星迁移到类太阳恒星水冰线内部的时间尺度和主导物理机制。在这里，我们总结了该计划前14个月的结果，重点是我们为HPF定制的RV管道，测量年轻太阳类似物的固有近红外RV活动，并对恒星抖动的潜在人口水平分布进行建模。我们证明了在2 m s $^{-1}$以下的K2标准HD 3765使用最小二乘匹配方法提取精确的RV水平的天空稳定性。基于我们计划中至少进行三次RV测量的29颗恒星的子样本，我们发现中值RMS水平为34 m s $^{-1}$。这几乎是一个因素，低于60米秒的$^{-1}$的光学中值RMS水平的比较样品与相似的年龄和光谱型作为我们的目标。该子样本的近红外抖动测量结果与$μ=4.15$和$σ=1.02$的对数正态母体分布吻合良好。最后，通过编译RMS值从以前的行星搜索计划，我们表明，G和K矮星的近红外抖动一般随着年龄的衰减以类似的方式光学波长，虽然有一个较浅的斜率和较低的整体价值年龄$\lesssim$ 1 Gyr。
英文摘要：
We present early results from the Epoch of Giant Planet Migration program, a precise RV survey of over one hundred intermediate-age ($\sim$20$-$200 Myr) G and K dwarfs with the Habitable-Zone Planet Finder spectrograph (HPF) at McDonald Observatory's Hobby-Eberly Telescope (HET). The goals of this program are to determine the timescale and dominant physical mechanism of giant planet migration interior to the water ice line of Sun-like stars. Here, we summarize results from the first 14 months of this program, with a focus on our custom RV pipeline for HPF, a measurement of the intrinsic near-infrared RV activity of young Solar analogs, and modeling the underlying population-level distribution of stellar jitter. We demonstrate on-sky stability at the sub-2 m s$^{-1}$ level for the K2 standard HD 3765 using a least-squares matching method to extract precise RVs. Based on a subsample of 29 stars with at least three RV measurements from our program, we find a median RMS level of 34 m s$^{-1}$. This is nearly a factor of 2 lower than the median RMS level in the optical of 60 m s$^{-1}$ for a comparison sample with similar ages and spectral types as our targets. The observed near-infrared jitter measurements for this subsample are well reproduced with a log-normal parent distribution with $μ=4.15$ and $σ=1.02$. Finally, by compiling RMS values from previous planet search programs, we show that near-infrared jitter for G and K dwarfs generally decays with age in a similar fashion to optical wavelengths, albeit with a shallower slope and lower overall values for ages $\lesssim$1 Gyr.
Study of the impact of the post-MS evolution of the host star on the orbits of close-in planets. II. A giant planet in a close-in orbit around the RGB star HIP63242
Late-infall-induced formation of giant planets, multigenerational planetesimals, and disk substructures
Max Planck Institute for Solar System Research（马克斯·普朗克太阳系研究所）；University of Chicago（芝加哥大学）；Ludwig-Maximilians-Universität München（慕尼黑大学）；Exzellenzcluster ORIGINS（ORIGINS卓越集群）
