# Improved measurements of the absolute branching fractions of the inclusive decays $D^{+(0)}\to\phi X$

## TL;DR

This paper reports precise measurements of the inclusive decay branching fractions of D mesons to phi and X, using BESIII data, and finds no significant CP asymmetry.

## Contribution

It provides the first separate measurements of D and anti-D decays to phi X and improves the precision of these branching fractions.

## Key findings

- Branching fractions: D+→φX at (1.135±0.034±0.031)% and D0→φX at (1.091±0.027±0.035)%
- No significant CP asymmetry observed in these decays
- First time measurements of D and anti-D decays to φX are reported

## Abstract

By analyzing 2.93 fb$^{-1}$ of $e^+e^-$ annihilation data taken at the center-of-mass energy $\sqrt s=$ 3.773 GeV with the BESIII detector, we determine the branching fractions of the inclusive decays $D^+\to\phi X$ and $D^0\to\phi X$ to be $(1.135\pm0.034\pm0.031)\%$ and $(1.091\pm0.027\pm0.035)\%$, respectively, where $X$ denotes any possible particle combination. The first uncertainties are statistical and the second systematic. We also determine the branching fractions of the decays $D\to\phi X$ and their charge conjugate modes $\bar{D}\to\phi \bar{X}$ separately for the first time, and no significant CP asymmetry is observed.