Characteristics of solar-like oscillations of secondary red clump stars
Abstract
We calculated the populations of core-helium-burning (CHeB) stars and found that the secondary red clump (SRC) stars can form an SRC peak in the distributions of the frequency of maximum seismic amplitude () and mean large-frequency separation () of CHeB stars when metallicity 0.02. The and of CHeB stars are dependent not only on He core mass but on H-shell burning. The SRC peak is composed of the CHeB stars with mass roughly between the critical mass M_{Hef} and M_{Hef}+0.2 while He core mass is between about 0.33 and 0.36 M_{sun}. The location of the SRC peak can be affected by the mixing-length parameter , metallicity , and overshooting parameter . A decrease in or increase in or leads to a movement of the SRC peak towards a lower frequency. However, the change in and only slightly affects the value of M_{Hef} but the variation in can significantly affects the value of M_{Hef}. Thus the SRC peak might aid in determining the value of M_{Hef} and calibrating . In addition, the effects of convective acceleration of SRC stars and the of `semi-degenerate' stars decreasing with mass result in the appearance of a shoulder between about 40 and 50 hz in the \dnu{} distribution. However, the convective acceleration of stars with M < M_{Hef} leads to the deficit in the distribution between about 9 and 20 hz{}. Moreover, the value of the parameter of the relation between and for the populations with M > M_{Hef} is obviously larger than that for the populations with \dmhef{}.
Keywords
Cite
@article{arxiv.1202.2017,
title = {Characteristics of solar-like oscillations of secondary red clump stars},
author = {Wuming Yang and Xiangcun Meng and Shaolan Bi and Zhijia Tian and Kang Liu and Tanda Li and Zhongmu Li},
journal= {arXiv preprint arXiv:1202.2017},
year = {2015}
}
Comments
10 pages, 15 figures. Accepted for publication in MNRAS