2021 年 3 巻 p. 4-
The resonance hypothesis for the cause of the decreasing event in the pulsation amplitude of the Cepheid component of Polaris is proposed. If Polaris is at the center of the 2:1 resonance between the first and the fourth overtone modes, we can estimate the mass and luminosity from the results of the linear nonadiabatic pulsation models using resonance conditions. The estimated stellar parameters from the resonance hypothesis are within the possible parameter range.