The standard stellar models for α Cen A and B have been constructed without resorting to the arbitrary constraint of the Solar mixing length ratio. Assuming that the chemical compositions and the ages of the two stars are the same, series of models have been constructed. Using the observational constraints, [Z/X], we were able to constrain the number of the 'possible' models. We find that utilizing the observational constraints of [Z/X] the best models for α Cen system are with the initial Z = 0.03, X = 0.66~0.67. In particular, the primary and the secondary stars may have the same mixing length ratio 1.6~1.7, which is the same as that of the calibrated Solar model. And, the age of the system is about 5.4 Gyr. Finally, the large spacing of the p-modes is predicted to be 104 ± 4μHz for α Cen A.

• YONG-CHEOL KIM(Center for Space Astrophysics, Yonsei University)