A Fast Approximate Approach to Microlensing Survey Analysis
A Fast Approximate Approach to Microlensing Survey Analysis
复制标题
微透镜测量分析的快速近似方法
作者：
S. Khakpash;M. Penny;J. Pepper
微透镜可以用来发现质量范围很广的外行星，其轨道超过100 Au，甚至是自由漂浮的行星。宽视场红外巡天望远镜（WFIRST）的使命将利用微透镜现象，通过监测1000万颗恒星，发现150，000个微透镜现象，从而发现大约1600个行星。对每个微透镜事件进行建模，特别是涉及两个或更多个透镜的微透镜事件，通常是复杂和耗时的，并且使用当前方法分析数千个WFIRST微透镜事件可能是不可行的。在这里，我们提出了一种算法，能够快速评估数以千计的模拟WFIRST二元透镜微透镜光变曲线，返回的透镜系统的物理参数的估计。我们发现，该算法可以恢复行星和星星之间的预测分离很好的低质量比的事件，也可以估计质量比的数量级的事件与广泛和密切的焦散拓扑结构。
Microlensing can be used to discover exoplanets of a wide range of masses with orbits beyond ∼1 au, and even free-floating planets. The Wide Field Infrared Survey Telescope (WFIRST) mission will use microlensing to discover approximately 1600 planets by monitoring ∼100 million stars to find ∼50,000 microlensing events. Modeling each microlensing event, especially the ones involving two or more lenses, is typically complicated and time consuming, and analyzing thousands of WFIRST microlensing events is possibly infeasible using current methods. Here, we present an algorithm that is able to rapidly evaluate thousands of simulated WFIRST binary-lens microlensing light curves, returning an estimate for the physical parameters of the lens systems. We find that this algorithm can recover projected separations between the planet and the star very well for low-mass-ratio events, and can also estimate mass ratios within an order of magnitude for events with wide and close caustic topologies.