Stellar orbital eccentricity and formation of thick disk of the Galaxy based on LAMOST

doi:10.7523/j.issn.2095-6134.2016.06.003

Abstract

Abstract:

Based on LAMOST data,we use F/G main-sequence star sample to study the orbital eccentricity distri bution of the thick-disk stars in the Galaxy. The thick-disk stars are identified by spatial position and metallicity, and the contamination from the thin-disk stars is considered. We find that the observed thick-disk stellar orbital eccentricity distribution has a peak at low eccentricity (~0.2) and it extends to high eccentricity (e~0.8). We compare our results with the four thick-disk formation models, and our results are in the best agreement with the gas-rich merger model.

Key words: thick-disk formation, eccentricity, solar neighborhood

CLC Number:

P156.5

JING Yingjie, DU Cuihua. Stellar orbital eccentricity and formation of thick disk of the Galaxy based on LAMOST[J]. , 2016, 33(6): 736-740.

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