Using chiral perturbation theory we calculate the imaginary parts of the ${\mathit{K}}_{\mathit{L}}$→${\mathrm{\pi }}^{+}$${\mathrm{\pi }}^{\mathrm{-}}$${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{-}}$ form factors that arise from ππ→${\mathrm{\pi }}^{+}$${\mathrm{\pi }}^{\mathrm{-}}$ and ππ→${\mathrm{\pi }}^{+}$${\mathrm{\pi }}^{\mathrm{-}}$γ* rescattering. We discuss their influence on CP-violating variables in ${\mathit{K}}_{\mathit{L}}$→${\mathrm{\pi }}^{+}$${\mathrm{\pi }}^{\mathrm{-}}$${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{-}}$. © 1996 The American Physical Society.

• Received 22 June 1995

DOI:https://doi.org/10.1103/PhysRevD.53.4078