标题： 土星卫星泰坦的盘平均近红外相曲线中观察到的极端前向散射 显示英文标题

标题： Extreme Forward Scattering Observed in Disk-Averaged Near-Infrared Phase Curves of Titan

摘要： 土星拥有浓厚且多雾的大气层，是我们的太阳系中理解光散射过程的关键天体。 NASA的卡西尼任务在2004年至2017年间对土卫六进行了监测，所得到的数据集包括大量全盘观测数据。 一旦进行空间积分，这些全盘观测数据揭示了土卫六的相位依赖性亮度，这可以作为其他恒星周围多雾世界可能外观的类比。 为了探索土卫六的相位曲线，我们提出了一个管道，用于处理卡西尼号可见光和红外映射光谱仪（VIMS）获取的全盘土卫六观测数据，波长范围为0.9--5.1$\mu$m。该管道的应用发现了超过4,400个质量良好的空间和光谱分辨的数据立方体，然后将其集成到土卫六的盘面上，以产生相位角范围为2--165\degree{}的相位曲线。 接近全相位的光谱为土卫六的几何反照率提供了有用的近似，从而扩展了先前工作的光谱覆盖范围。 卡西尼号VIMS相位曲线中的新月相亮度增强通常比光学波长处的类似结果更为极端，这可以通过大气透明度和雾霾散射过程来解释。 这些结果为针对系外行星的光谱模型提供了验证机会，并且有助于理解极端气溶胶前向散射可能如何影响系外行星的观测和解释。 显示英文摘要

摘要： Titan, with its thick and hazy atmosphere, is a key world in our solar system for understanding light scattering processes. NASA's Cassini mission monitored Titan between 2004 and 2017, where the derived dataset includes a large number of whole disk observations. Once spatially integrated, these whole disk observations reveal Titan's phase-dependent brightness which can serve as an analog for how hazy worlds might appear around other stars. To explore Titan's phase curve, we present a pipeline for whole disk Titan observations acquired by the Cassini Visual and Infrared Mapping Spectrometer (VIMS) spanning 0.9--5.1 $\mu$m. Application of the pipeline finds over 4,400 quality spatially- and spectrally-resolved datacubes that were then integrated over Titan's disk to yield phase curves spanning 2--165\degree{} in phase angle. Spectra at near-full phase provide a useful approximation for Titan's geometric albedo, thus extending the spectral coverage of previous work. Crescent phase brightness enhancements in the Cassini VIMS phase curves are often more extreme than analogous results seen at optical wavelengths, which can be explained by atmospheric transparency and haze scattering processes. These results provide validation opportunities for exoplanet-focused spectral models and also shed light on how extreme aerosol forward scattering could influence exoplanet observations and interpretations.