Seismic probing of the first dredge-up event through the eccentric red-giant & red-giant spectroscopic binary KIC9163796

摘要: Binaries in double-lined spectroscopic systems provide a homogeneous set of stars. Differences parameters, such as age or initial conditions, which otherwise would have strong impact on the stellar evolution, can be neglected. The observed differences are determined by difference mass between two components. ratio with much higher accuracy than actual mass. In this work, we aim to study eccentric binary system KIC9163796, whose components very close and both low-luminosity red-giant stars from four years Kepler space photometry high-resolution spectroscopy Hermes. Mass radius primary were through asteroseismology 1.39+/-0.06 Mo 5.35+/-0.09 Ro, resp. From spectral disentangling was found 1.015+/-0.005 that secondary is ~600K hotter primary. Evolutionary models place components, early advanced stage first dredge-up event branch. theoretical primary, derived internal rotational gradient. grid models, measured lithium abundance compared predictions. surface rotation light curve resembles orbital period within 10 days. radial gradient core 6.9+2.0/-1.0. agreement seismic result indicates full convective envelope rotating quasi-rigidly. compatible rigid radiative zone during main sequence. Because many constraints offered oscillating systems, objects important test beds evolution.