The evolution of rotation and activity for FGK dwarfs in LAMOST– <i>Kepler</i> field

ABSTRACT Based on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) and Gaia surveys, we compute the convective turnover time-scales of stars with the mass range of 0.7–1.4 ${\rm M}_{\odot }$ using the mesa code. We provide a catalogue of 10 400 FGK dwarfs in the LAMOST–Kepler field, including Rossby number Ro, rotation periods ${ P}_{\rm rot}$, photometric activity proxy $S_{\rm ph}$, and chromospheric activity index $R^{+}_{\rm HK}$. The relations between both activity indices and Ro can be characterized by the saturated, decay, and flat regimes. In the flat regime, the $S_{\rm ph}$ remains nearly constant while the $R^{+}_{\rm HK}$ exhibits an enhancement as Ro increases for F dwarfs. In the decay regime, all stars exhibit uniform decay behaviour in both $S_{\rm ph}$–Ro and $R^{+}_{\rm HK}$–Ro relations. In the saturated regime, GK dwarfs display a significant $S_{\rm ph}$ dip, while only K dwarfs exhibit a pronounced $R^{+}_{\rm HK}$ dip. Moreover, the Ro range of this dip aligns with the spin-down stalling observed in open cluster studies, suggesting a possible origin in the core–envelope coupling senario. Additionally, the results show that the Sun falls within the transition from decay to flat regime in both activity-Ro diagrams. The results will improve the understanding of the connection among convection, rotation, and magnetic fields for solar-like stars.

Authors

Institutions

Publication Details

Journal
Monthly Notices of the Royal Astronomical Society
Published
2025-11-06
DOI
https://doi.org/10.1093/mnras/staf1792
Primary Topic
Stellar, planetary, and galactic studies
Type
article
Field-Weighted Citation Impact
0.00

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

The evolution of rotation and activity for FGK dwarfs in LAMOST– Kepler field

Xianfei Zhang, Tiancheng Sun, Yuqing Chen, Tanda Li et al.
Monthly Notices of the Royal Astronomical Society
Stellar, planetary, and galactic studies
article

The evolution of rotation and activity for FGK dwarfs in LAMOST– Kepler field

Xianfei Zhang, Tiancheng Sun, Yuqing Chen, Tanda Li, Shaolan Bi, Liu Long, Xinyi Zhang, Jie Yu, Mengjie Li, Jinghua Zhang, Yaguang Li, Lifei Ye, Jianzhao Zhou
article en

Abstract

ABSTRACT Based on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) and Gaia surveys, we compute the convective turnover time-scales of stars with the mass range of 0.7–1.4 ${\rm M}_{\odot }$ using the mesa code. We provide a catalogue of 10 400 FGK dwarfs in the LAMOST–Kepler field, including Rossby number Ro, rotation periods ${ P}_{\rm rot}$, photometric activity proxy $S_{\rm ph}$, and chromospheric activity index $R^{+}_{\rm HK}$. The relations between both activity indices and Ro can be characterized by the saturated, decay, and flat regimes. In the flat regime, the $S_{\rm ph}$ remains nearly constant while the $R^{+}_{\rm HK}$ exhibits an enhancement as Ro increases for F dwarfs. In the decay regime, all stars exhibit uniform decay behaviour in both $S_{\rm ph}$–Ro and $R^{+}_{\rm HK}$–Ro relations. In the saturated regime, GK dwarfs display a significant $S_{\rm ph}$ dip, while only K dwarfs exhibit a pronounced $R^{+}_{\rm HK}$ dip. Moreover, the Ro range of this dip aligns with the spin-down stalling observed in open cluster studies, suggesting a possible origin in the core–envelope coupling senario. Additionally, the results show that the Sun falls within the transition from decay to flat regime in both activity-Ro diagrams. The results will improve the understanding of the connection among convection, rotation, and magnetic fields for solar-like stars.

Monthly Notices of the Royal Astronomical SocietyVol. 544(2)
Australian National University (AU), Ministry of Education of the People's Republic of China (CN), University of Hawaii System (US), Yunnan University (CN), Chinese Academy of Sciences (CN), Beijing Normal University (CN), Mount Stromlo Observatory (AU), Université Bourgogne Franche-Comté (FR), Astronomy and Space (AU), National Astronomical Observatories (CN), Xiangtan University (CN), Nanjing University (CN)
National Aeronautics and Space Administration, European Space Agency, National Natural Science Foundation of China, Chinese Academy of Sciences, China Postdoctoral Science Foundation, National Development and Reform Commission, Science Mission Directorate, National Astronomical Observatories, Chinese Academy of Sciences
Openalex Percentile: Top 77%
Stellar, planetary, and galactic studies
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.