DMPP-4: candidate sub-Neptune mass planets orbiting a naked-eye star
DMPP-4: candidate sub-Neptune mass planets orbiting a naked-eye star
复制标题
DMPP-4：围绕肉眼恒星运行的候选亚海王星质量行星
DOI：
10.1093/mnras/stad2109
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Barnes J
中科院分区：
文献类型：
--
作者：
Barnes J
我们给出了非常明亮的F星∼-4(HD 184960)附近的径向速度测量结果。异常低的CaiiH&K辐射表明，围绕低活动主恒星运行的行星造成了质量损失。具有∼10m S−1振幅的径向速度周期变率在a&>4年时间尺度上持续。尽管四个TESS扇区不同时的光度可变性支持一颗不活跃恒星的观点，但我们识别了周期性的光度信号，并找到了恒星活动的光谱证据。我们使用包括开普勒信号数目NP作为自由参数的后验抽样算法来检验和比较(1)纯开普勒式模型，(2)具有线性活动关联的开普勒式模型和(3)具有高斯过程的开普勒式模型。具有一个开普勒量和准周期高斯过程的首选模型表明，行星的周期为d，相应的最小质量为Fm⊕。如果在更长的时间尺度上没有进一步的高时间分辨率观测，我们不能确定地排除具有两个候选行星的纯粹的开普勒式模型，它们具有最小质量的M⊕和d以及相应的最小质量的Fm⊕。候选行星位于海王星沙漠下部包络以下的区域。持续的质量损失可能来自高度辐照的行星，或者来自系统中尚未被探测到的天体。
We present radial velocity measurements of the very bright (V∼ 5.7) nearby F star, DMPP-4 (HD 184960). The anomalously low CaiiH&K emission suggests mass-loss from planets orbiting a low activity host star. Periodic radial velocity variability with ∼10 m s−1amplitude is found to persist over a >4 yr time-scale. Although the non-simultaneous photometric variability in fourTESSsectors supports the view of an inactive star, we identify periodic photometric signals and also find spectroscopic evidence for stellar activity. We used a posterior sampling algorithm that includes the number of Keplerian signals,Np, as a free parameter to test and compare (1) purely Keplerian models (2) a Keplerian model with linear activity correlation and (3) Keplerian models with Gaussian processes. A preferred model, with one Keplerian and quasi-periodic Gaussian process indicates a planet with a period ofd and corresponding minimum mass ofM⊕. Without further high-time resolution observations over a longer time-scale, we cannot definitively rule out the purely Keplerian model with two candidates planets withd, minimum massM⊕andd and corresponding minimum mass ofM⊕. The candidate planets lie in the region below the lower-envelope of the Neptune Desert. Continued mass-loss may originate from the highly irradiated planets or from an as yet undetected body in the system.