Isospin Mixing In The Isobaric-Analog State Derived From The (P, N(Ias)(P)Over-Tilde) Reaction On Ce-140, Yb-172,Yb-174,Yb-196 And Pb-208

An exclusive coincidence experiment of the (p, n(IAS) (p) over tilde) reaction was carried out for the first time by measuring decay protons from the isobaric analog states (IAS) formed by the (p,n) reactions on Ce-140, Yb-172,Yb-174,Yb-176, and Pb-208 at E-p = 35 MeV. Spreading widths of the IAS were deduced from the escape and total widths. Results were compared with a recent theory of isospin mixing, corroborating the conclusion that contributions from the isovector monopole state, especially that from the T-component instead of that from T-0-1 one, were important to explain quantitatively the experimental A-dependence of spreading widths.