Magnetic activity of the spotted dwarf AP149 in the α Persei open cluster  

作　　者：Xiang-Song Fang Sheng-Hong Gu Sze-Leung Cheung Ho-Keung Hui Chi-Tai Kwok Kam-Cheung Leung 

机构地区：[1]National Astronomical Observatories / Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011, China [2]Graduate University of Chinese Academy of Sciences, Beijing 100049, China [3]Ho Koon Nature Education cum Astronomical Centre, Sik Sik Yuen, Hong Kong, China [4]Hong Kong Astronomical Society, Hong Kong, China

出　　处：《Research in Astronomy and Astrophysics》2010年第3期253-265,共13页天文和天体物理学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.10373023 and 10773027);a grant from the Sik Sik Yuen of Hong Kong,China

摘　　要：The simultaneous photometric and spectroscopic observations of the spotted G dwarf AP149 in the young open cluster α Persei are analyzed here. We reconstruct the observed light curves with a two-starspot model by means of a light curve modeling technique, and find that the active regions shift oppositely along longitude on a time scale of one day. Combining with the observational data obtained by other groups, we discuss the evolution of spotted regions in the photosphere, and find that its starspots evolve not only on a short time scale but also on a long time scale. The pure chromospheric emissions for Ca IIHK and Hβ lines are derived by using the spectral subtraction technique. The variation of Ca IIHK lines＇ excess emission is spatially correlated to the starspot regions. There is no clear rotational modulation for the Hβ line＇s excess emission, probably due to the contamination of prominence emission.The simultaneous photometric and spectroscopic observations of the spotted G dwarf AP149 in the young open cluster α Persei are analyzed here. We reconstruct the observed light curves with a two-starspot model by means of a light curve modeling technique, and find that the active regions shift oppositely along longitude on a time scale of one day. Combining with the observational data obtained by other groups, we discuss the evolution of spotted regions in the photosphere, and find that its starspots evolve not only on a short time scale but also on a long time scale. The pure chromospheric emissions for Ca IIHK and Hβ lines are derived by using the spectral subtraction technique. The variation of Ca IIHK lines＇ excess emission is spatially correlated to the starspot regions. There is no clear rotational modulation for the Hβ line＇s excess emission, probably due to the contamination of prominence emission.

关 键 词：stars： activity -- stars： late-type -- stars： spots -- stars： individual AP149 

分 类 号：P114.4[天文地球—天文学] P157.8