论文标题
TFAW调查。 I.基于小波的K2光曲线的deoisis。在K2运动中发现和验证两个新的地球大小的行星1
TFAW survey. I. Wavelet-based denoising of K2 light curves. Discovery and validation of two new Earth-sized planets in K2 campaign 1
论文作者
论文摘要
首次将基于小波的分解和剥落方法\ texttt {tfaw}首次应用于\ texttt {everest 2.0} - 校正光曲线，以进一步提高几乎所有K2观测活动的光度精度（C1-C8，C12-C18）。两种方法的性能均以6个小时的组合差分光度精度（CDPP），模拟的过境检测效率和行星表征在不同的SNR状态下进行评估。平均而言，\ texttt {tfaw}中位6hr cdpp是$ \ sim $ 30 $ \％$ $ \％$比\ texttt {everest 2.0}获得的所有观察活动都要好。 Using the \texttt{transit least-squares} (\texttt{TLS}) algorithm, we show that the transit detection efficiency for simulated Earth-Sun-like systems is $\sim$8.5$\times$ higher for \texttt{TFAW}-corrected light curves than for \texttt{EVEREST 2.0} ones.使用两个确认的外球星的光曲线，K2-44 B（高-SNR）和K2-298 B（Low-SNR），我们表明\ texttt {tfaw}可以产生更好的MCMC后验分布，与被拆迁的不稳定性相符的过境参数，但具有较小的不遗产和较小的可信度间隔。我们使用\ texttt {tfaw}改进的光度精度和\ texttt {tls}的增强信号检测效率的增强弱信号的增强，以搜索K2观测活动中的新的过境候选活动1。 201170410.02，半径为1.047 $^{+0.276} _ { - 0.257} r _ {\ oplus} $行星绕M型明星和Epic 201757695.02，带有半径为0.908 $^{+0.059} _ { - 0.064} r _ {\ oplus} $行星绕k-type star。 EPIC 201757695.02是有史以来第9-最小的星球，也是所有K2运动中第39-最小的星球。
The wavelet-based detrending and denoising method \texttt{TFAW} is applied for the first time to \texttt{EVEREST 2.0}-corrected light curves to further improve the photometric precision of almost all K2 observing campaigns (C1-C8, C12-C18). The performance of both methods is evaluated in terms of 6 hr combined differential photometric precision (CDPP), simulated transit detection efficiency, and planet characterization in different SNR regimes. On average, \texttt{TFAW} median 6hr CDPP is $\sim$30$\%$ better than the one achieved by \texttt{EVEREST 2.0} for all observing campaigns. Using the \texttt{transit least-squares} (\texttt{TLS}) algorithm, we show that the transit detection efficiency for simulated Earth-Sun-like systems is $\sim$8.5$\times$ higher for \texttt{TFAW}-corrected light curves than for \texttt{EVEREST 2.0} ones. Using the light curves of two confirmed exoplanets, K2-44 b (high-SNR) and K2-298 b (low-SNR), we show that \texttt{TFAW} yields better MCMC posterior distributions, transit parameters compatible with the cataloged ones but with smaller uncertainties and narrows the credibility intervals. We use the combination of \texttt{TFAW}'s improved photometric precision and \texttt{TLS} enhancement of the signal detection efficiency for weak signals to search for new transit candidates in K2 observing campaign 1. We report the discovery of two new K2-C1 Earth-sized planets statistically validated, using the \texttt{vespa} software: EPIC 201170410.02, with a radius of 1.047$^{+0.276}_{-0.257}R_{\oplus}$ planet orbiting an M-type star, and EPIC 201757695.02, with a radius of 0.908$^{+0.059}_{-0.064}R_{\oplus}$ planet orbiting a K-type star. EPIC 201757695.02 is the 9-th smallest planet ever discovered in K2-C1, and the 39-th smallest in all K2 campaigns.
