Theoretical analysis of direct $CP$ violation and differential decay width in $D^{\pm }\to {\pi }^{\pm }{\pi }^{+}{\pi }^{-}$ in phase space around the resonances ${\rho }^0(770)$ and $f_0(500)$

Abstract

We perform a theoretical study on direct $CP$ violation in $D^{\pm }\to {\pi }^{\pm }{\pi }^{+}{\pi }^{-}$ in phase space around the intermediate states ${\rho }^0(770)$ and $f_0(500)$. The possible interference between the amplitudes corresponding to the two resonances is taken into account, and the relative strong phase of the two amplitudes is treated as a free parameter. Our analysis shows that by properly chosen the strong phase, both the $CP$ violation strength and differential decay width accommodate to the experimental results.

Comments: 15 pages, 5 figures