A Sky-Subtraction Algorithm for LAMOST Using Two-Dimensional Sky-Background Modeling

Abstract A novel algorithm is proposed for the sky subtraction of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) based on two-dimensional sky background modeling. Different from the standard fiber spectrum data processing techniques, a two-dimensional sky background model can be obtained with the new algorithm and sky subtraction can now be performed as an earlier step, before the spectrum extraction. In this study, experiments are performed on simulated data based on the LAMOST project to analyze the accuracy and the effectiveness. The results show that the proposed algorithm can give a more effective sky subtraction than the method that is currently used for LAMOST.