A systematic fitting scheme for caustic-crossing microlensing events
A systematic fitting scheme for caustic-crossing microlensing events
复制标题
焦散交叉微透镜事件的系统拟合方案
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
L. Wyrzykowski
中科院分区：
文献类型：
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作者：
N. Kains;A. Cassan;K. Horne;M. Albrow;S. Dieters;P. Fouqué;J. Greenhill;A. Udalski;M. Zub;D. Bennett;M. Dominik;J. Donatowicz;D. Kubas;Y. Tsapras;T. Anguita;V. Batista;J. Beaulieu;S. Brillant;M. Bode;D. Bramich;M. Burgdorf;J. Caldwell;K. Cook;C. Coutures;D. Prester;U. Jørgensen;S. Kane;J. Marquette;R. Martin;J. Menzies;K. Pollard;N. Rattenbury;K. Sahu;C. Snodgrass;I. Steele;C. Vinter;J. Wambsganss;A. Williams;M. Kubiak;G. Pietrzyński;I. Soszyński;O. Szewczyk;M. Szymański;K. Ulaczyk;L. Wyrzykowski
我们概述了一种方法，用于拟合二元透镜焦散交叉微透镜事件的基础上提出的替代模型参数化和详细的卡桑。作为我们的方法的一个例子，我们提出了OGLE-2007-BLG-472的分析，一个双峰的银河系微透镜事件的源穿越整个焦散结构在不到三天。为了确定所有可能的模型，我们进行了广泛的搜索的参数空间，然后通过细化的参数与马尔可夫链蒙特卡罗算法。我们在参数空间中发现了一些低χ2区域，这导致了几个不同的竞争最佳模型。我们检查每个参数，并估计其物理特性。我们发现，我们的拟合策略位于几个极小值，很难找到与其他建模策略，因此是一个更合适的方法来适应这种类型的事件。
We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology, we present an analysis of OGLE-2007-BLG-472, a double-peaked Galactic microlensing event with a source crossing the whole caustic structure in less than three days. In order to identify all possible models we conduct an extensive search of the parameter space, followed by a refinement of the parameters with a Markov Chain Monte Carlo algorithm. We find a number of low-χ2 regions in the parameter space, which lead to several distinct competitive best models. We examine the parameters for each of them, and estimate their physical properties. We find that our fitting strategy locates several minima that are difficult to find with other modelling strategies and is therefore a more appropriate method to fit this type of event.