论文标题
用光度法和光谱法限制过渡行星的污垢性
Constraining the oblateness of transiting planets with photometry and spectroscopy
论文作者
论文摘要
快速行星旋转会导致行星的平衡形状被植入。虽然行星的含性主要是通过检查光度传输光曲线中的细微入口和出口特征来探测的，但我们研究了填充性对光谱rossiter-mclaughlin（RM）信号的影响。我们发现，一个巨大的星球，星球与星形半径比为0.15且类似土星的扁态性为0.098，可能会导致光谱特征，幅度高达1.1 ms $^{ - 1} $，可通过高精确光谱仪（例如咖啡仪）（例如咖啡仪）检测到。我们还发现，对于跨旋转的恒星和具有旋转轨道未对准的行星的转移，光谱填充信号被特别放大，从而使它们比某些过境方向的光度信号更为突出。我们比较了光度法和光谱法中填充性的可检测性，并发现光度光曲线比光谱曲线比光谱RM信号更敏感，这主要是因为它们可以通过更高的节奏进行采样以更好地探测填充性注入和egress anmaly。但是，对透明行星的光曲线和RM信号的联合分析提供了对行星底漆的更准确和精确的估计。因此，浓缩咖啡以及正在进行的和即将到来的光度仪器（例如苔丝，Cheops，Plato和JWST）将在测量行星底漆方面非常有用。
Rapid planetary rotation can cause the equilibrium shape of a planet to be oblate. While planetary oblateness has mostly been probed by examining the subtle ingress and egress features in photometric transit light curves, we investigate the effect of oblateness on the spectroscopic Rossiter-McLaughlin (RM) signals. We found that a giant planet, with planet-to-star radius ratio of 0.15 and Saturn-like oblateness of 0.098, can cause spectroscopic signatures with amplitudes up to 1.1 ms$^{-1}$ which is detectable by high-precision spectrographs such as ESPRESSO. We also found that the spectroscopic oblateness signals are particularly amplified for transits across rapidly rotating stars and for planets with spin-orbit misalignment thereby making them more prominent than the photometric signals at some transit orientations. We compared the detectability of oblateness in photometry and spectroscopy and found that photometric light curves are more sensitive to detecting oblateness than the spectroscopic RM signals mostly because they can be sampled with higher cadence to better probe the oblateness ingress and egress anomaly. However, joint analyses of the light curve and RM signal of a transiting planet provides more accurate and precise estimate of the planet's oblateness. Therefore, ESPRESSO alongside ongoing and upcoming photometric instruments such as TESS, CHEOPS, PLATO and JWST will be extremely useful in measuring planet oblateness.
