https://doi.org/10.1140/epjc/s2004-02038-5
theoretical physics
Non-factorizable contribution to 
1
Department of Physics, Yantai University, 264005, Yantai, China
2
CCAST (World Laboratory), P.O. Box 8730, 100080, Beijing, China
* e-mail: cjy@ytu.edu.cn
For charmed color-suppressed 
decay, non-factorizable contributions are expected to be leading, and the naive factorization description breaks down. We study the 1/m
b
power-suppressed non-factorizable effect in , which is due to soft exchange between the emitted heavy-light quark pair and the 
system, in the framework of QCD light-cone sum rules. The resulting correction to the decay amplitude is found to be numerically comparable with the corresponding factorizable piece, estimated to be at about (50-
of the latter. The relevant parameter a
2 receives a positive number contribution, due to the factorizable correction and the power-suppressed soft effect. Our findings could be crucial to a phenomenological understanding of the 
decay.
© Springer-Verlag, 2004
