# ICHEP2018 SEOUL

Jul 4 – 11, 2018
COEX, SEOUL
Asia/Seoul timezone

## Precise measurement of the $D^{*}(2010)^+ - D^+$ mass difference

Jul 5, 2018, 5:40 PM
15m
101 (COEX, Seoul)

### 101

#### COEX, Seoul

Parallel Strong Interactions and Hadron Physics

### Speaker

Dr Liang Sun (Wuhan University (CN))

### Description

We measure the mass difference, $\Delta m_+$, between the $D^{*}(2010)^+$ and the $D^+$, using the decay chain $D^{*}(2010)^+\to D^+ \pi^0$ with $D^+ \to K^- \pi^+ \pi^+$. The data were recorded with the BABAR detector at center-of-mass energies at and near the $\Upsilon(4S)$ resonance, and correspond to an integrated luminosity of approximately $468 \, \mbox{fb}^{-1}$. We measure   $\Delta m_+ = \left(140\,601.0 \pm 6.8\,[{\rm stat}] \pm 12.9 \,[{\rm syst}]\right) \, \mbox{keV}$.
We combine this result with a previous BaBar measurement of $\Delta m_0\equiv m(D^{*}(2010)^+) - m (D^0)$ to obtain  $\Delta m_D = m(D^+) - m(D^0) = \left(4\,824.9 \pm 6.8\,[{\rm stat}] \pm12.9\,[{\rm syst}]\right) \, \mbox{keV}$.
These results are compatible with, and approximately five times more precise than, previous world averages.

### Primary authors

Fabio Anulli (Sapienza Universita e INFN, Roma I (IT)) Dr Liang Sun (Wuhan University (CN))