Possible bound state of the double heavy meson-baryon system

Abstract

We calculate the two-pion exchange potential between a heavy meson and a heavy baryon. We find this potential is as strong as the one-pion exchange potential between two heavy mesons and is enough to bind ${\Lambda }_b-\bar{B}$. Though our result is sensitive to the cut-off, the value of the cut-off is in the reasonable region.

Comments: 11 pages, 3 figures, replace the old verson which does not correspond to the published version