70 citations · 472 across the 20 of their papers we have counts for
20 papers
Detection of Ubiquitous Circumbinary Matter in Hot Subdwarfs Formed from Common-Envelope Ejections
Jiangdan Li, Christian Wolf, Jiao Li +7
The formation of compact binary systems is largely driven by their evolution through a common envelope (CE) phase, crucial for understanding phenomena such as type Ia supernovae an…
Revisit NGC 5466 Tidal Stream with , SDSS/SEGUE and LAMOST
Yong Yang, Jing-Kun Zhao, Miho N. Ishigaki +5
By mining the data from EDR3, SDSS/SEGUE DR16 and LAMOST DR8, 11 member stars of the NGC 5466 tidal stream are detected and 7 of them are newly identified. To reject contami…
High-α-Metal-Rich stars in the LAMOST-MRS survey and its connection with the galactic bulge
Haopeng Zhang, Yuqin Chen, Gang Zhao +6
We report the detection of a large sample of high--metal-rich stars on the low giant branch with dex in the LAMOST-MRS survey. This special group corresponds to a…
Partitioning the Galactic Halo with Gaussian Mixture Models
Xilong Liang, Yuqin Chen, Jingkun Zhao +1
The Galactic halo is supposed to form from merging with nearby dwarf galaxies. In order to probe different components of the Galactic halo, we have applied the Gaussian Mixture Mod…
Nearly 30,000 late-type main-sequence stars with stellar age from LAMOST DR5
Jiajun Zhang, Jingkun Zhao, Terry D. Oswalt +3
We construct a sample of nearly 30,000 main-sequence stars with 4500K 5000K and stellar ages estimated by the chromospheric activityage relation. This sample is u…
Most Lithium-rich Low-mass Evolved Stars Revealed as Red Clump stars by Asteroseismology and Spectroscopy
Hong-Liang Yan, Yu-Tao Zhou, Xianfei Zhang +19
Lithium has confused scientists for decades at almost each scale of the universe. Lithium-rich giants are peculiar stars with lithium abundances over model prediction. A large frac…
A new moving group in the Local Arm
Xilong Liang, Jingkun Zhao, Yuqin Chen +5
We present a new moving group clustered in kinematics, spatial position and elemental abundances. Its spatial position is around the center of the Local Arm of the Milky Way. A con…
Is NGC 5824 the Core of the Progenitor of the Cetus Stream?
Jiang Chang, Zhen Yuan, Xiang-Xiang Xue +5
A large number of new members (150) of the Cetus Stream (CS) were identified from their clustering features in dynamical space using 6D kinematic data by combining LAMOST DR5…
Hot subdwarf stars identified in Gaia DR2 with spectra of LAMOST DR6 and DR7 I. Single-lined spectra
Zhenxin Lei, Jingkun Zhao, Péter Németh +1
182 single-lined hot subdwarf stars are identified by using spectra from the sixth and seventh data release (DR6 and DR7) of the Large Sky Area Multi-Object Fibre Spectroscopic Tel…
Elemental abundances distributions in (R, ) plane with LAMOST DR5 and Gaia DR2
Xilong Liang, Jingkun Zhao, Yuqin Chen +4
Since Gaia DR2 was released, many velocity structures in the disk have been revealed such as large scale ridge-like patterns in the phase space. Both kinematic information and stel…
Stellar chromospheric activity and age relation from open clusters in the LAMOST Survey
Jiajun Zhang, Jingkun Zhao, Terry D. Oswalt +5
We identify member stars of more than 90 open clusters in the LAMOST survey. With the method of Fang et al.(2018), the chromospheric activity (CA) indices logR'CaK for 1091 member…
Searching for Hot Subdwarf Stars in LAMOST DR1-II. Pure spectroscopic identification method for hot subdwarfs
Zhenxin Lei, Yude Bu, Jingkun Zhao +2
Employing a new machine learning method, named hierarchical extreme learning machine (HELM) algorithm, we identified 56 hot subdwarf stars in the first data release (DR1) of the La…
New hot subdwarf stars identified in Gaia DR2 with LAMOST DR5 spectra -- II
Zhenxin Lei, Jingkun Zhao, Péter Németh +1
388 hot subdwarf stars have been identified by using the Hertzsprung-Russell (HR) diagram built from the second data release (DR2) of the Gaia mission. By analyzing their observed…
A Hint of Three-section Halo as Seen from the APOGEE DR14
Y. Q. Chen, G. Zhao, X. X. Xue +4
Based on the [Fe/H] versus [Mg/Fe] diagram and distances from APOGEE data release 14, we compare the spatial distributions, the l-Vlos diagram and the abundance gradients between h…
New hot subdwarf stars identified in Gaia DR2 with LAMOST DR5 spectra
Zhenxin Lei, Jingkun Zhao, Németh Péter +1
We selected 4593 hot subdwarf candidates from the Gaia DR2 Hertzsprung-Russell (HR) diagram. By combining the sample with LAMOST DR5, we identified 294 hot subdwarf stars, includin…
On the radial metallicity gradient and radial migration effect of the Galactic disk
Yunpeng Jia, Yuqin Chen, Gang Zhao +4
We study the radial metallicity gradient as a function of [Mg/Fe] and with the help of a guiding radius based on the Apache Point Observatory Galactic Evolution…
A new Hyper-Runaway star discovered from LAMOST and GAIA: ejected almost in the galactic rotation direction
Yin-Bi Li, A-Li Luo, Gang Zhao +11
In this paper, we report the discovery of a new late-B type unbound hyper-runaway star (LAMOST-HVS4) from the LAMOST spectroscopic surveys. According to its atmospheric parameters,…
Spectral feature extraction for DB white dwarfs through machine learning applied to new discoveries in the SDSS DR12 and DR14
Xiao Kong, A-Li Luo, Xiang-Ru Li +3
Using a machine learning (ML) method, we mine DB white dwarfs (DBWDs) from the Sloan Digital Sky Survey (SDSS) Data Release (DR) 12 and DR14. The ML method consists of two parts: f…
Stellar activity with LAMOST - II. Chromospheric activity in open clusters
Xiang-Song Fang, Gang Zhao, Jing-Kun Zhao +1
We use the LAMOST spectra of member stars in Pleiades, M34, Praesepe, and Hyades to study how chromospheric activity vary as a function of mass and rotation at different age. We me…
A Catalog of Moving Group Candidates in The Solar Neighborhood
Jingkun Zhao, Gang Zhao, Yuqin Chen
Based on the kernel estimator and wavelet technique, we have identified 22 moving group candidates in the solar neighborhood from a sample which includes around 14,000 dwarfs and 6…