Tensor correlation in 4He with the tensor-optimized shell model

Abstract

We study the characteristics of the tensor correlation in 4He using a shell model type method. We treat the tensor force explicitly by performing a configuration-mixing calculation in the 2p2h basis and include single-particle states up to intermediately high angular momenta. We adopt the Gaussian expansion method for the quantitative description of the spatial shrinkage of the single-particle states to optimize the tensor correlation. We are able to describe the full strength of the tensor correlation for 4He in the shell model type method by realizing convergence. We call this model the tensor-optimized shell model. It is found that in 4He, three specific 2p2h configurations are strongly coupled with the (0s) 4 configuration due to the characteristic features of the tensor operator.