MK-like spectral classification for hot subdwarf stars with LAMOST spectra

Xuan Zou; Zhenxin Lei

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arXiv · 2407.17062

MK-like spectral classification for hot subdwarf stars with LAMOST spectra

Xuan Zou·Zhenxin Lei

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Abstract

An MK-like spectral classification has been conducted for 1224 hot subdwarf stars with LAMOST DR9 low-resolution spectra. The whole sample was divided into four categories according to the spectral line characteristics: He-normal, He-weak, He-strong C and He-strong. Each selected spectrum was assigned a spectral class, a luminosity class and an helium class by comparing the line depth and width with standard spectra selected in LAMOST. Relationships between atmospheric parameters and spectral classification were also presented.

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Xuan Zou, Zhenxin Lei. 2024-07-24. MK-like spectral classification for hot subdwarf stars with LAMOST spectra. https://arxiv.org/abs/2407.17062

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