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arXiv · 1808.01242

Tracing the origin of moving groups I. The γ Leo moving group with high resolution spectra from the Subaru Telescope

Xilong Liang·Jingkun Zhao·Gang Zhao·Wako Aoki·Ishigaki Miho·Matsuno Tadafumi·Yuqin Chen·Xiaoming Kong·Jianrong Shi·Qianfan Xing
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Abstract

We present chemical abundances of 15 stars in the γ Leo moving group based on high-resolution spectra with the Subaru High Dispersion Spectrograph. The sample was picked up by applying wavelet transform to UVW velocity compo- nents of stars in the solar neighbourhood. Both photometric and spectroscopic method have been used to determine the stellar parameters of stars. Abun- dances of 11 elements including Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Y and Ba are measured. Our results show that the member stars display a wide metallicity distribution with abundance ratios similar to Milky way disk stars. We presume that the γ Leo moving group is originated from dynamical effects probably related to the Galactic spiral arms.

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Xilong Liang, Jingkun Zhao, Gang Zhao, Wako Aoki, Ishigaki Miho, Matsuno Tadafumi, Yuqin Chen, Xiaoming Kong, Jianrong Shi, Qianfan Xing. 2018-08-02. Tracing the origin of moving groups I. The γ Leo moving group with high resolution spectra from the Subaru Telescope. https://doi.org/10.3847/1538-4357%2Faacf8a

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