Amplitude Analysis and Branching Fraction Measurement of $D^+ \to \pi^+\pi^0\pi^0$

TL;DR

This paper reports the first amplitude analysis of the decay $D^+ o \pi^+\pi^0\pi^0$, measuring branching fractions, dominant intermediate states, and CP asymmetries using BESIII data.

Contribution

It provides the first detailed amplitude analysis of this decay mode, including measurements of branching fractions and CP asymmetries, with data from BESIII.

Findings

Dominant $D^+ o ho(770)^+\pi^0$ component with a branching fraction of $(3.08\pm0.10_{ m stat.}\pm0.05_{ m syst.}) imes10^{-3}$.

Total branching fraction of $D^+ o \pi^+\pi^0\pi^0$ measured as $(4.84\\pm0.05_{ m stat.}\\pm0.05_{ m syst.}) imes10^{-3}$.

CP asymmetries measured for specific amplitudes and over the entire phase space.

Abstract

We present the first amplitude analysis of the hadronic decay $D^+\to\pi^+\pi^0\pi^0$, using $e^{+}e^{-}$ collision data collected with the BESIII detector at a center-of-mass energy of 3.773~GeV, corresponding to an integrated luminosity of 20.3~fb$^{-1}$. The fit fractions of the intermediate processes are measured, in which the $D^+ \to \rho(770)^+\pi^0$ component is found to be dominant with a branching fraction of $(3.08\kern0.15em\pm\kern0.15em0.10_{\rm stat.}\pm0.05_{\rm syst.})\times10^{-3}$. Based on the amplitude analysis, the branching fraction of $D^+ \to \pi^+\pi^0\pi^0$ is measured to be $(4.84\kern0.1em\pm\kern0.1em0.05_{\rm stat.}\kern0.1em\pm\kern0.1em0.05_{\rm syst.})\times10^{-3}$. In addition, the CP asymmetries, both for specific amplitudes and integrated over the entire phase space, are measured.