Study of the effect of the tensor correlation on the alpha clustering in 8Be with the charge- and parity-projected Hartree-Fock method

We study the effect of the tensor correlation in the alpha clustering in 8Be. We take as the wave function of the alpha particle the one calculated by the charge- and parity-projected Hartree- Fock method, which was proposed by us recently. We use the wave function in a cluster-model calculation. The expectation value of the potential energy from the tensor force is almost double of that in the alpha particle. The energy surface as the function of the relative distance of two alpha particles becomes much steeper in an inner region by the inclusion of the tensor correlation in the wave function of the alpha particle. This is caused by the p-state mixing induced by the tensor correlation. By superposing the wave function with different relative distances, the reasonable binding energy of 8Be is obtained.