The dependence of stellar magnetic activity on stellar parameters is inspired by the chromospheric activity studies based on the large-scale spectroscopic surveys. The main objective of this project is to provide the chromospheric activity parameter database for the LAMOST Low-Resolution Spectroscopic Survey (LRS) spectra of solar-like stars and explore the overall property of stellar chromospheric activity. The Ca II H and K lines were employed to construct indicators for assessing and studying the chromospheric activity of solar-like stars.
We investigated the widely used bolometric- and photospheric-calibrated chromospheric activity index $R'_ HK $, derived from the method in the classic literature ($R'_ HK,classic $) and the method based on the PHOENIX model ($R'_ HK,PHOENIX $).
Since the detailed stellar atmospheric parameters, effective temperature ($T_ eff $), surface gravity ($ and metallicity Fe/H ) are available for LAMOST, we estimated the chromospheric activity index $R'_ HK,PHOENIX $, along with the corresponding bolometric calibrated index $R_ HK,PHOENIX $, taking these parameters into account. We provided the database of the derived chromospheric activity parameters for 1,122,495 LAMOST LRS spectra of solar-like stars.
Our calculations show that $ HK,PHOENIX $ is approximately linearly correlated with $ HK,classic K