120 citations · 946 across the 56 of their papers we have counts for
26 papers · 1 filter
A Broken Clock Is Right Twice a Day: [Ce/Mg] Is Not a Universal Chemical Clock
Liam O. Dubay, Jennifer A. Johnson, James W. Johnson +14
The ratio of -process to -element enrichment () has been proposed as a ``chemical clock,'' or a means to estimate stellar ages. However, the age-- relation vari…
The Open Cluster Chemical Abundances and Mapping Survey XI. First Gradients from SDSS/MWM BOSS Determined Clusters
Jonah M. Otto, Peter M. Frinchaboy, John Donor +13
The Milky Way Mapper program in the fifth generation of the Sloan Digital Sky Survey (SDSS-V/MWM) has observed millions of stars, thousands of them in open clusters. The Open Clust…
The Twentieth Data Release of the Sloan Digital Sky Survey: First All-Sky BOSS Spectra, eROSITA-SDSS-V Mapper Coordinated Observations, and a Preview of the Local Volume Mapper
SDSS Collaboration, Mojgan Aghakhanloo, David Aguilar +273
This paper presents the twentieth data release (DR20) from the Sloan Digital Sky Survey, the third data release of its fifth generation (SDSS-V). SDSS-V is a panoptic spectroscopy…
Long Tidal Tails of NGC 5024 Hidden in LMS-1 and NGC 5053 Tidal Streams
Xianhao Ye, Yong Yang, Jingkun Zhao +3
We report the discovery of long tidal tails associated with the globular cluster (GC) NGC 5024. A modified matched filter applied to Gaia DR3 data reveals a broad stellar stream sp…
Mapping the Milky Way with Gaia Bp/Rp spectra-IV: the broken and asymmetric density profile of the stellar disk traced by a large sample of red clumps
Wenbo Wu, Yuqin Chen, Jianhui Lian +10
This study explores the density profile of the stellar disk, radially and azimuthally, based on approximately 8.4 million red clump stars selected from Gaia Bp/Rp spectra. After co…
Galactic Archaeology with the Subaru `Ōnohi`ula Prime Focus Spectrograph Strategic Program
Masashi Chiba, Rosemary F. G. Wyse, Evan N. Kirby +48
The recently commissioned Subaru `Ōnohi`ula Prime Focus Spectrograph (PFS) will obtain spectra from nearly 2,400 fibers that cover 1.24 square degrees. The 360 night Subaru Strateg…
Moving Groups in the Solar Neighborhood with Gaia, APOGEE, GALAH, and LAMOST: Dynamical Effects Gather Gas and the Ensuing Star Formation Plays an Important Role in Shaping the Stellar Velocity Distributions
Xilong Liang, Suk-Jin Yoon, Jingkun Zhao
With Gaia, APOGEE, GALAH, and LAMOST data, we investigate the positional, kinematic, chemical, and age properties of nine moving groups in the solar neighborhood. We find that each…
Four-hundred Very Metal-poor Stars Studied with LAMOST and Subaru. III. Dynamically Tagged Groups and Chemodynamical Properties
Ruizhi Zhang, Tadafumi Matsuno, Haining Li +9
Very metal-poor (VMP) stars record the signatures of early accreted galaxies, making them essential tools for unraveling the early stages of Galaxy formation. Understanding the ori…
Detection of the actinide Th in an r-process-enhanced star with accretion origin
Xing Qianfan, Zhao Gang, Aoki Wako +4
The thorium and six second-peak r-process element (56<Z<72) abundances are determined for the alpha-poor star LAMOST J1124+4535 based on a high-resolution spectrum obtained with th…
Candidate Members of the VMP/EMP Disk System of the Galaxy from the SkyMapper and SAGES Surveys
Jihye Hong, Timothy C. Beers, Young Sun Lee +15
Photometric stellar surveys now cover a large fraction of the sky, probe to fainter magnitudes than large-scale spectroscopic surveys, and are relatively free from the target-selec…
On the Migration Origin of the Hercules Moving Group with GAIA, LAMOST, APOGEE, and GALAH Surveys
Xilong Liang, Suk-Jin Yoon, Jingkun Zhao +3
Using Gaia DR3 data and the wavelet transformation technique, we study the substructures of the Hercules moving group (HMG): Hercules 1 (H1) and Hercules 2 (H2). Spectroscopic surv…
Beyond spectroscopy. II. Stellar parameters for over twenty million stars in the northern sky from SAGES DR1 and Gaia DR3
Yang Huang, Timothy C. Beers, Hai-Bo Yuan +18
We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 mi…
The Stellar Abundances and Galactic Evolution Survey (SAGES) -- -- I. General Description and the First Data Release (DR1)
Zhou Fan, Gang Zhao, Wei Wang +35
The Stellar Abundances and Galactic Evolution Survey (SAGES) of the northern sky is a specifically-designed multi-band photometric survey aiming to provide reliable stellar paramet…
The Spectacular Tidal Tails of Globular Cluster M3 (NGC 5272)
Yong Yang, Jing-Kun Zhao, Xin-Zhe Tang +2
We provide a detailed analysis on tidal tails of the globular cluster M3 (NGC 5272). We first discover clear extra-tidal structures with slight S-shape near the cluster. This inspi…
A Dwarf Galaxy Debris Stream Associated with Palomar 1 and the Anticenter Stream
Yong Yang, Jing-Kun Zhao, Xian-Hao Ye +2
We report the discovery of a new stream (dubbed as Yangtze) detected in Data Release 3. The stream is at a heliocentric distance of 9.12 kpc and spans nearly 27 by…
Existence of Tidal Tails for the Globular Cluster NGC 5824
Yong Yang, Jing-Kun Zhao, Miho N. Ishigaki +5
Context. Several dynamically cold streams have been associated with certain globular clusters (GCs) based on orbital energies and angular momenta. Some of these streams are surpris…
A New Cold Stream near the Southern Galactic Pole
Yong Yang, Jing-Kun Zhao, Xiang-Xiang Xue +2
We report the discovery of a cold stream near the southern Galactic pole (dubbed as SGP-S) detected in Early Data Release 3. The stream is at a heliocentric distance of $\si…
Revisit of open clusters UPK 39, UPK 41 and PHOC 39 : a new binary open cluster found
Xianhao Ye, Jingkun Zhao, Terry D. Oswalt +2
We investigate the three open clusters near Aquila Rift cloud, named as UPK 39 (\texttt{c1} hereafter), UPK 41 (\texttt{c2} hereafter) in Sim et al. (2019) and PHOC 39 (\texttt{c3}…
The stellar parameters and elemental abundances from low-resolution spectra I: 1.2 million giants from LAMOST DR8
Zhuohan Li, Gang Zhao, Yuqin Chen +2
As a typical data-driven method, deep learning becomes a natural choice for analysing astronomical data nowadays. In this study, we built a deep convolutional neural network to est…
A spectroscopic study of blue supergiant stars in Local Group spiral galaxies: Andromeda and Triangulum
Cheng Liu, Rolf-Peter Kudritzki, Gang Zhao +4
Low-resolution LAMOST and Keck spectra of blue supergiant stars distributed over the disks of the Local Group spiral galaxies M 31 and M 33 are analyzed to determine stellar effect…
High-precision chemical abundances of Galactic building blocks. II. Revisiting the chemical distinctness of the Helmi streams
Tadafumi Matsuno, Emma Dodd, Helmer H. Koppelman +6
Context: The Helmi streams are a kinematic substructure whose progenitor is likely a dwarf galaxy. Although 20 years have passed since their discovery, it is still unclear whether…
Tracing the Origin of Moving Groups. III. Detecting Moving Groups in The LAMOST DR7
Yong Yang, Jingkun Zhao, Jiajun Zhang +2
We revisit the moving groups (MGs) in the solar neighborhood with a sample of 91969 nearby stars constructed from LAMOST DR7. Using the wavelet technique and Monte Carlo simulation…
Chemical abundances of primary stars in the Sirius-like binary systems
X. M. Kong, G. Zhao, J. K. Zhao +6
Study of primary stars lying in Sirius-like systems with various masses of WD companions and orbital separations is one of the key aspects to understand the origin and nature of Ba…
Stellar Stream Candidates in the Solar Neighborhood Found in the LAMOST DR3 and TGAS
Xilong Liang, Jingkun Zhao, Terry D. Oswalt +3
We have cross-matched the LAMOST DR3 with the Gaia DR1 TGAS catalogs and obtained a sample of 166,827 stars with reliable kinematics. A technique based on the wavelet transform was…