A5075024026- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Magnetic properties of thin films
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Analytical Chemistry and Chromatography
- Traditional Chinese Medicine Analysis
- Ga2O3 and related materials
- Genetics and Plant Breeding
- Nuclear physics research studies
- Complex Systems and Decision Making
- GaN-based semiconductor devices and materials
- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Coal Properties and Utilization
- Metal and Thin Film Mechanics
- Quantum and electron transport phenomena
- Chromatography in Natural Products
- Plant Physiology and Cultivation Studies
Shandong Agricultural University
2024-2025
Peking University
2016-2024
Yunnan University
2018-2024
Astronomy and Space
2024
Kavli Institute for Theoretical Sciences
2018-2019
Beijing Normal University
2011-2015
Yunnan Observatories
2013
Shaanxi Normal University
2006
Fudan University
2004
We present new three-dimensional (3D) interstellar dust reddening maps of the Galactic plane in three colours, E(G-Ks), E(Bp-Rp) and E(H-Ks). The have a spatial angular resolution 6 arcmin covers over 7000 deg$^2$ for longitude 0 deg $<$ $l$ 360 latitude $|b|$ $10$ deg. are constructed from robust parallax estimates Gaia Data Release 2 (Gaia DR2) combined with high-quality optical photometry DR2 infrared 2MASS WISE surveys. estimate colour excesses, E(H-Ks), 56 million stars machine learning...
We present the second release of value-added catalogues LAMOST Spectroscopic Survey Galactic Anticentre (LSS-GAC DR2). The values radial velocity $V_{\rm r}$, atmospheric parameters --- effective temperature $T_{\rm eff}$, surface gravity log$g$, metallicity [Fe/H], $\alpha$-element to iron (metal) abundance ratio [$\alpha$/Fe] ([$\alpha$/M]), elemental abundances [C/H] and [N/H], absolute magnitudes ${\rm M}_V$ M}_{K_{\rm s}}$ deduced from 1.8 million spectra 1.4 unique stars targeted by...
We present estimates of stellar age and mass for 0.93 million Galactic disk main sequence turn-off sub-giant stars from the LAMOST Spectroscopic Surveys. The ages masses are determined by matching with isochrones using Bayesian algorithm, utilizing effective temperature $T_{\rm eff}$, absolute magnitude ${\rm M}_V$, metallicity [Fe/H] $\alpha$-element to iron abundance ratio [$\alpha$/Fe] deduced spectra. Extensive examinations suggest robust. overall sample have a median error 34 per cent...
We present a large, homogeneous catalogue of molecular clouds within 4 kpc from the Sun at low Galactic latitudes ($|b|$ $<$ 10\degr) with unprecedented accurate distance determinations. Based on three-dimensional dust reddening map and estimates colour excesses distances over 32 million stars presented in Chen et al, we have identified 567 dust/molecular hierarchical structure identification method obtained their by model fitting algorithm. The typical uncertainty is less than 5 per cent....
Abstract We present a comprehensive study of the kinematic properties different Galactic disk populations, as defined by chemical abundance ratios and stellar ages, across large volume (4.5 ≤ R 15.0 kpc ∣ Z 3.0 kpc), using LAMOST-Gaia red clump sample stars. determine median velocities for various spatial population bins, finding large-scale bulk motions; example, wave-like behavior in radial velocity, north–south discrepancy azimuthal velocity warp signal vertical amplitudes dependences...
We present a detailed determination and analysis of 3D stellar mass distribution the Galactic disk for mono-age populations using sample 0.93 million main-sequence turnoff subgiant stars from LAMOST Surveys. Our results show following. (1) All younger than 10 Gyr exhibit strong flaring, which is accompanied by dumpy vertical density profile that best described sechn function with index depending on both radius age. (2) Asymmetries wave-like oscillations are presented in radial direction,...
We present a catalog of stellar age and mass estimates for sample 640 986 red giant branch (RGB) stars the Galactic disk from LAMOST Spectroscopic Survey (DR4).The RGB are distinguished clump utilizing period spacing derived spectra with machine learning method based on kernel principal component analysis (KPCA).Cross-validation suggests our is capable distinguishing RC only 2 per cent contamination rate signal-to-noise ratio (SNR) higher than 50.The these determined their KPCA by taking...
We investigate the morphology and kinematics of Galactic spiral structure based on a new sample O- early B-type stars. select 6858 highly confident OB star candidates from combined data VST Photometric H α Survey Data Release 2 (VPHAS+ DR2) Gaia (Gaia DR2). Together with O-B2 stars literature, we build consisting 14 880 stars, all parallax uncertainties smaller than 20 per cent. The sample, hitherto largest one robust distance proper motion estimates, covers plane distances up to 6 kpc Sun....
Obtaining accurate and precise masses ages for large numbers of giant stars is great importance unraveling the assemblage history Galaxy. In this paper, we estimate 6940 red branch (RGB) with asteroseismic parameters deduced from Kepler photometry stellar atmospheric derived LAMOST spectra. The typical uncertainties mass a few per cent, that age ∼20 cent. sample reveal two separate sequences in age–[α/Fe] relation – high-α sequence older than ∼8 Gyr low-α composed ranging younger 1 to 11...
We present a new catalogue of 18 080 radial velocity standard stars selected from the APOGEE data. These RV are observed at least three times and have median stability ($3\sigma_{\rm RV}$) around 240 m s$^{-1}$ over time baseline longer than 200 days. They largely distributed in northern sky could be extended to southern by future APOGEE-2 survey. Most red giants ($J - K_{\rm s} \ge 0.5$) owing target selection criteria. Only about ten per cent them main-sequence stars. The $H$ band...
ABSTRACT To gain a better understanding of the Andromeda galaxy M31 and its role in Local Group, measuring mass precisely is essential. In this work, we have constructed rotation curve out to ∼125 kpc using 13 679 objects obtained from various sources, including LAMOST data release 9 (LAMOST DR9), DESI survey, relevant literature. We divide all our sample into bulge, disc, halo components. For sources measured their circular velocities by kinematic model with asymmetric drift corrections....
Double or extended main-sequence turn-offs (DMSTOs) and dual red clump (RC) were observed in intermediate-age clusters, such as NGC 1846 419. the DMSTOs are interpreted that cluster has two distinct stellar popula- tions with differences age of about 200-300 Myr but same metallicity. The RC is a result prolonged star formation. Using population-synthesis method, we calculated evolutions binary-star population (BSP). We found binary interactions merging can reproduce color-magnitude diagrams...
We present a catalog of 5,290 RR Lyrae stars (RRLs) with metallicities estimated from spectra the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) Sloan Extension (SEGUE) surveys. Nearly 70 per cent them (3,642 objects) also have systemic radial velocities measured. Given pulsating nature RRLs, metallicity estimates are based on individual exposures, by matching synthetic templates. The measured fitting observed velocity as function phase assuming an empirical template...
Recent observations have revealed a population of $\alpha$-element abundances enhanced giant stars with unexpected high masses ($\gtrsim$1 $M_\odot$) from asteroseismic analysis and spectroscopy. Assuming single-star evolution, their imply young ages ($\tau<6$Gyr) incompatible the canonical Galactic chemical evolution scenario. Here we study chemistry kinematics large sample such $\alpha$-rich, high-mass red branch (RGB) drawn LAMOST spectroscopic surveys. Using Gaia, found these share same...
Abstract The chemical composition of the Sun is still a highly controversial issue. No solar model has yet been able to simultaneously reproduce lithium and beryllium abundances, along with helioseismic results, including rotation profile. Lithium are fragile elements that sensitive physical conditions, as well transport mixing processes within below convective zone (CZ). Uncovering mechanisms responsible for depletion Li Be in crucial using them tools understand stellar interiors associated...
Abstract The statistical characteristics of double main-sequence (MS) binaries are essential for investigating star formation, binary evolution, and population synthesis. Our previous study proposed a machine learning-based method to identify MS from single stars using mock data the Chinese Space Station Telescope (CSST). We further utilized detection efficiencies an empirical mass ratio distribution estimate fraction within sample. To validate effectiveness this method, we conducted more...
Aims. We constructed models of the structure and evolution stars including diffusion extra-mixing caused by rotation to estimate stellar parameters solar twin 18 Scorpii.
Photometric data from the Xuyi Schmidt Telescope Survey of Galactic Anticentre (XSTPS-GAC) and Sloan Digital Sky (SDSS) are used to derive global structure parameters smooth components Milky Way. The data, which cover nearly 11 000 deg2 sky area full range latitude, allow us construct a globally representative model. number density distribution halo stars is fitted with an oblate spheroid that decays by power law. best fitting yields axis ratio power-law index κ = 0.65 p 2.79, respectively....
We present a three-dimensional (3D) extinction analysis in the region towards supernova remnant (SNR) S147 (G180.0–1.7) using multiband photometric data from Xuyi Schmidt Telescope Photometric Survey of Galactic Anticentre (XSTPS-GAC), 2MASS and WISE. isolate previously unrecognized dust structure likely to be associated with SNR S147. The structure, which we term as 'S147 cloud', is estimated have distance d = 1.22 ± 0.21 kpc, consistent conjecture that pulsar PSR J0538 + 2817. cloud...
We report the discovery of two new unbound hypervelocity stars (HVSs) from LAMOST spectroscopic surveys. They are respectively a B2V type star ~ 7 M$_{\rm \odot}$ with Galactic rest-frame radial velocity 502 km/s at Galactocentric radius 21 kpc and B7V 4 408 30 kpc. The origins HVSs not clear given their currently poorly measured proper motions. However, future data releases Gaia should provide motion measurements accurate enough to solve this problem. ongoing surveys expected yield more...
We select from Paper I a sample of 306 massive star clusters observed with the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) in vicinity fields M31 and M33 determine their metallicities, ages masses. Metallicities are estimated by fitting integrated spectra stellar synthesis population (SSP) models pixel-to-pixel spectral technique. Ages for most young also derived multi-band photometric measurements model energy distributions (SEDs). The cluster span wide range, several...
RV variable stars are important in astrophysics. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic survey has provided ~ 6.5 million stellar spectra its Data Release 4 (DR4). During the survey, 4.7 unique sources were targeted and 1 observed repeatedly. probabilities of being variables estimated by comparing radial velocity variations with simulated ones. We build a catalog 80,702 candidates probability greater than 0.60 analyzing duplicate-observed...
We have investigated the metallicity distributions of mono-age stellar populations across disc $6 \lesssim R 12$\,kpc and $|Z| 2$\,kpc using samples selected from main-sequence turn-off sub-giant (MSTO-SG) stars targeted by LAMOST Galactic Spectroscopic surveys. Both mean values profiles exhibit significant variations with age position. confirm that oldest ($>11$\,Gyr) nearly flat radial [Fe/H] gradients at all heights above but show negative vertical gradients. For younger than 11\,Gyr,...
Abstract We have investigated the distributions of stellar azimuthal and radial velocity components V Φ R in vertical position–velocity plane Z – across Galactic disk 6.34 ≲ 12.34 kpc using a Gaia -LAMOST sample stars. As found previous works, exhibit significant spiral patterns. The also show clear quadrupole patterns, which are consequence well-known tilt ellipsoid. observed patterns phase space vary strongly with positions. spirals become more relaxed as increases. strongest at −2° <...