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arXiv · 1011.3892

Data characterization using artificial-star tests: performance evaluation

Yi Hu·Licai Deng·Richard de Grijs·Qiang Liu
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Abstract

Traditional artificial-star tests are widely applied to photometry in crowded stellar fields. However, to obtain reliable binary fractions (and their uncertainties) of remote, dense, and rich star clusters, one needs to recover huge numbers of artificial stars. Hence, this will consume much computation time for data reduction of the images to which the artificial stars must be added. In this paper, we present a new method applicable to data sets characterized by stable, well-defined point-spread functions, in which we add artificial stars to the retrieved-data catalog instead of the raw images. Taking the young Large Magellanic Cloud cluster NGC 1818 as an example, we compare results from both methods and show that they are equivalent, while our new method saves significant computational time.

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Yi Hu, Licai Deng, Richard de Grijs, Qiang Liu. 2010-11-17. Data characterization using artificial-star tests: performance evaluation. https://doi.org/10.1086/658162

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