Systematics of Soft Final-State Interactions inBDecays

By using very general and well established features of soft strong interactions we show, contrary to conventional expectations, that (i) soft final-state interactions (FSI) do not disappear for large $m_B$, (ii) inelastic rescattering is expected to be the main source of soft FSI phases, and (iii) FSI which interchange charge and/or flavors are suppressed by a power of $m_B$, but are quite likely to be significant at $m_B\simeq 5\mathrm{GeV}$. We briefly discuss the influence of these interactions on tests of CP violation and on theoretical calculations of weak decays.