论文标题
Binning总是犯罪吗？时间平衡对系外行星相曲线的影响
Is binning always sinning? The impact of time-averaging for exoplanet phase curves
论文作者
论文摘要
我们探索有限的整合时间或时间分解如何影响外部球星相曲线的分析。我们提供分析公式来说明这种效果，或者如果忽略了，以估计检索到的参数中的潜在偏差。如预期的那样，由于它们在更长的时间尺度上的变化更平滑，因此相比，相曲线比过境更重，而不会引起严重的偏见。在具有周期$ p $的正弦相曲线的最简单情况下，集成时间$ΔT$通过缩放系数$ \ text {sinc} {\ left（πΔT / p \ right）} $降低了其幅度，而无需更改相位或形状。我们还提供公式来预测相曲线观测值合理的参数误差线。我们的发现通过合成和真实数据集进行了测试，包括未建模的天体物理信号和/或仪器系统效应。使用Spitzer数据的测试表明，由于高频相关噪声的校正，binning会影响超出预测的最佳拟合参数。最后，我们总结了关键指南，以加快对系外行相曲线的分析，而无需在检索到的参数中引入明显的偏见。
We explore how finite integration time or temporal binning can affect the analysis of exoplanet phase-curves. We provide analytical formulae to account for this effect or, if neglected, to estimate the potential biases in the retrieved parameters. As expected, due to their smoother variations over longer time-scales, phase curves can be binned more heavily than transits without causing severe biases. In the simplest case of a sinusoidal phase curve with period $P$, the integration time $Δt$ reduces its amplitude by the scaling factor $\text{sinc}{ \left ( πΔt / P \right ) }$, without altering its phase or shape. We also provide formulae to predict reasonable parameter error bars from phase-curve observations. Our findings are tested with both synthetic and real datasets, including unmodelled astrophysical signals and/or instrumental systematic effects. Tests with the Spitzer data show that binning can affect the best-fitting parameters beyond predictions, due to the correction of high-frequency correlated noise. Finally, we summarize key guidelines for speeding up the analysis of exoplanet phase curves without introducing significant biases in the retrieved parameters.
