Accepted Friday Oct 30, 2009
A new version of the generalized density-dependent cluster model is presented to describe an a particle tunneling through a deformed potential barrier. The microscopic deformed potential is numerically constructed in the double folding model by the multipole expansion method. The decay width is computed using the coupled-channel Schrödinger equation with outgoing wave boundary conditions. We perform a systematic calculation on a-decay half-lives of even-even nuclei ranging from Z=52 to Z=104, including 65 well-deformed ones. The calculated a-decay half-lives are found to be in good agreement with the experimental values. There also exists good agreement with the available experimental branching ratios for well-deformed systems.