(Semi-)leptonic D$_{(s)}$ decays at BESIII

Abstract

BESIII has collected

$2.93$ and

$6.32\,\mathrm{fb^{-1}}$ of e

$^+$ e

$^-$ collision data samples at

$3.773$ and

$4.178$ -

$4.226$ GeV, respectively. We will report precision measurements of

$f_{D_{(s)}}$ ,

$|V_{cs}|$ ,
and test of lepton flavor universality by studying the leptonic decays of

$D_s^+ \rightarrow l \nu$
with

$\tau^+ \rightarrow \rho^+ \nu$ ,

$\pi^+ \nu$ , and

$e^+ \nu \nu$ . We will also report the observation of
semileptonic decay of

$D^0 \rightarrow \rho^-\mu^+\nu$ and lepton flavor universality test, and the
studies of some other semileptonic decays, such as

$D_s^+ \rightarrow \pi^0\pi^0e^+\nu$ and

$D_s^+ \rightarrow K_s^0 K_s^0 e^+\nu$ .