The strength of the analog and Gamow-Teller giant resonances and hindrance of the 2νββ-decay rate

An approach for describing the hindrance of the nuclear 2νββ-decay amplitude is proposed. The approach is based on a new formula obtained by a model-independent transformation of the initial expression for the amplitude. This formula takes explicitly into account the hindrance of the decay-amplitude due to the presence of the collective Gamow-Teller state. Calculations are performed within the simplest version of the approach. Calculated and experimental 2νββ halve-lives are compared for a wide range of nuclei.