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arXiv · 1705.02084

Cosmic Ray Removal in Fiber Spectroscopic Image

Zhongrui Bai·Haotong Zhang·Hailong Yuan·Jeffrey L. Carlin·Guangwei Li·Yongheng Zhao·Zihuang Cao
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Abstract

Single-exposure spectra in large spectral surveys are valuable for time domain studies such as stellar variability, but there is no available method to eliminate cosmic rays for single-exposure, multi-fiber spectral images. In this paper, we describe a new method to detect and remove cosmic rays in multi-fiber spectroscopic single exposures. Through the use of two-dimensional profile fitting and a noise model that considers the position-dependent errors, we successfully detect as many as 80% of the cosmic rays and correct the cosmic ray polluted pixels to an average accuracy of 97.8%. Multiple tests and comparisons with both simulated data and real LAMOST data show that the method works properly in detection rate, false detection rate, and validity of cosmic ray correction.

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Zhongrui Bai, Haotong Zhang, Hailong Yuan, Jeffrey L. Carlin, Guangwei Li, Yongheng Zhao, Zihuang Cao. 2017-05-05. Cosmic Ray Removal in Fiber Spectroscopic Image. https://doi.org/10.1088/1538-3873%2F129%2F972%2F024004

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