Sub-m s-1 upper limits from a deep HARPS-N radial-velocity search for planets orbiting HD 166620 and HD 144579
Sub-m s-1 upper limits from a deep HARPS-N radial-velocity search for planets orbiting HD 166620 and HD 144579
复制标题
对围绕 HD 166620 和 HD 144579 运行的行星进行深度 HARPS-N 径向速度搜索的 Sub-m s-1 上限
DOI：
10.1093/mnras/stad2381
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发表时间：
2023
影响因子：
4.8
通讯作者：
Anna John A
中科院分区：
文献类型：
--
作者：
Anna John A
要达到寻找地球双胞胎所需的10 cm S−1精度，最大限度地减少恒星变化对径向速度(RV)测量的影响是一个关键挑战。自2012年以来，一直在与HARPS-N开展一项专门的计划，在北半球明亮的恒星周围进行盲目RV岩石行星搜索(RPS)。在这里，我们描述了在两个RPS目标HD 166620和HD 144579上对行星系统进行全面搜索的结果。使用波长域线剖面去相关矢量来缓解恒星活动，并使用跨维嵌套采样器对行星反射运动进行深入搜索，我们在两颗恒星的数据集中都没有发现显著的行星信号。我们通过数据拆分和注入恢复测试验证了结果。此外，我们还获得了HARPS-N房车的第95个百分位数的检测限值。我们发现，当使用标尺U向量校正恒星固有的可变性时，发现一颗低质量行星的可能性在很大的周期范围内显著增加。我们能够用Msini≤1 M⊕探测到轨道周期小于10 d的行星信号。我们证明了利用我们的解相关技术，我们能够探测到低至54 cm S−1的信号，这使我们更接近HARPS-N给出的50 cm S−1的定标下限。因此，我们表明，我们可以通过新的数据分析技术，利用高精度的径向速度数据，向下推向寻找地球类似物所需的RV精度。
Minimizing the impact of stellar variability in radial velocity (RV) measurements is a critical challenge in achieving the 10 cm s−1precision needed to hunt for Earth twins. Since 2012, a dedicated programme has been underway with HARPS-N, to conduct a blind RV rocky planets search (RPS) around bright stars in the Northern hemisphere. Here we describe the results of a comprehensive search for planetary systems in two RPS targets, HD 166620 and HD 144579. Using wavelength-domain line-profile decorrelation vectors to mitigate the stellar activity and performing a deep search for planetary reflex motions using a trans-dimensional nested sampler, we found no significant planetary signals in the data sets of either of the stars. We validated the results via data-splitting and injection recovery tests. Additionally, we obtained the 95th percentile detection limits on the HARPS-N RVs. We found that the likelihood of finding a low-mass planet increases noticeably across a wide period range when the inherent stellar variability is corrected for usingscalpelsU-vectors. We are able to detect planet signals withMsini≤ 1 M⊕for orbital periods shorter than 10 d. We demonstrate that with our decorrelation technique, we are able to detect signals as low as 54 cm s−1, which brings us closer to the calibration limit of 50 cm s−1demonstrated by HARPS-N. Therefore, we show that we can push down towards the RV precision required to find Earth analogues using high-precision radial velocity data with novel data-analysis techniques.