Sign Of Enhanced Three Alpha Matter Radius In Alpha + 12C Inelastic Scattering

Abstract

Nuclear radius of three α rotational state in 12 C with a life time of 10 −21 second, which has been expected to have much more extended radius than the ground 12 C nucleus, is speculated from systematic analysis of the differential cross section of the α + 12 C inelastic scattering. Present analysis predicts about 0.6 ∼ 1.0 fm enhancement in the matter radius of the three α rotational state in comparison to the normal radius of the ground state. The spatial extension of the three α rotational state is comparable to the extended radius observed in the neutron halo phenomena.Constraint on the recent ab-initio calculation for the 3α states in 12 C is also discussed.