Hard-soft factorization in B_c--> psi pi decay

Abstract

The width of $B_c^{+}\to \psi {\pi }^{+}$ decay is calculated in the framework of factorization of a hard gluon exchange and a soft binding of quarks in the heavy quarkonium, so that $\mathrm{BR}(B_c^{+}\to \psi {\pi }^{+})=2.0\pm 0.5$ \%.

Comments: 8 pages, LATEX file