Recent results of (semi)leptonic decays of charm hadrons at BESIII

Abstract

In this talk, we report the recent measurements of (semi)leptonic decays of charm mesons from the BESIII experiment, including $D^{+}\to {\mu }^{+}{\nu }_{\mu }$, $D^{+}\to {\tau }^{+}{\nu }_{\tau }$, $D^{+}\to {\eta }^{\prime }{\ell }^{+}{\nu }_{\ell }$, and $D^{0(+)}\to \bar{K}{\ell }^{+}{\nu }_{\ell }$ (where $\ell =e,\mu$). These measurements provide the most precise or first determinations to date of the CKM matrix elements $|V_{cs(d)}|$, the decay constant $f_{D^{+}}$, and the hadronic form factors $f_{+}^{D^{+}\to {\eta }^{\prime }}(0)$ and $f_{+}^{D\to \bar{K}}(0)$. Lepton flavor universality of $e-\mu$ and $\tau -\mu$ are also tested with these decays. Additionally, we present the first observation of the rare beta decay ${\Lambda }_c^{+}\to n{e}^{+}{\nu }_e$ with machine learning of Graph Neural Network.

contribution to the 2025 Electroweak session of the 59th Rencontres de Moriond