Related papers: Resonances in $D^0\to\pi^+\pi^-\ell^+\ell^-$ and s…
Physics of the up-type flavour offers unique possibilities of testing the Standard Model (SM) compared to the down-type flavour sector. Here, we discuss SM and New Physics (NP) contributions to the rare charm-meson decay $ D^0 \to \pi^+…
We revisit the Standard Model description of the recently measured rare decays $D^0\to\pi^+\pi^-\ell^+\ell^-$. Because of the effectiveness of the Glashow-Iliopoulos-Maiani mechanism in charm flavour-changing neutral currents, those decays…
We perform a comprehensive study of a number of rare charm decays, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects. For processes mediated by the…
We propose a model for $D^+ \to \pi^+ \pi^- \pi^+$ decays following experimental results which indicate that the two-pion interaction in the $S$-wave is dominated by the scalar resonances $f_0(600)/\sigma$ and $f_0(980)$. The weak decay…
Current experimental information on the charm meson decay observables in which the $c\to s\ell\nu_\ell$ transitions occur is well compatible with the Standard Model predictions. Recent precise lattice calculations of the $D_s$ meson decay…
Simple dynamics, few available decay channels, and extremely well controlled radiative and loop corrections, make pion and muon decays a sensitive means for testing the underlying symmetries, the universality of weak fermion couplings, as…
The observation of anomalies in the charged current $b\rightarrow c\bar{\ell}\nu_{\ell}$ transitions hints the possibility of the existence of new physics beyond the standard model. Inspired by the work done in the beauty quark sector, we…
$|\Delta c|=|\Delta u|=1$ processes are unique probes of flavor physics in the up-sector within and beyond the Standard Model (SM). SM tests with rare semileptonic charm meson decays are based on an approximate CP--symmetry, a superior…
We investigate the decays $D^0\to\pi^-\ell^+\nu$ and $D^0\to K^-\ell^+ \nu$, where $\ell$ is $e$ or $\mu$, using approximately 7 ${\rm fb}^{-1}$ of data collected with the CLEO III detector. We find $R_0\equiv {\cal B}(D^0\to…
We report the observation of the rare charm decay $D^0\rightarrow K^-\pi^+e^+e^-$, based on $468$ fb$^{-1}$ of $e^+e^-$ annihilation data collected at or close to the center-of-mass energy of the $Y(4S)$ resonance with the BaBar detector at…
We will discuss how the decays of charm mesons can be used to study light mesons spectroscopy, by presenting recent results of Dalitz plot analyses using data from Fermilab experiment E791. Emphasis will be on scalar mesons, which are found…
We consider the prospect of using the charm system as a laboratory for probing new physics. The theoretical expectations for rare charm meson decays, $D^0-bar D^0$ mixing, and charm quark asymmetries in $Z$ decays are examined in the…
Decays of the kind $B^0_{s,d}\to\ell^+\ell^-$ belong to the most favourable processes for probing the flavour structure of the Standard Model, with outstanding sensitivity to new (pseudo)-scalar contributions. While the branching ratio of…
We present a study of the rare charm meson decays $ D^{0}\rightarrow K^{+}K^{-}e^{+}e^{-} $, $ \pi^{+}\pi^{-}e^{+}e^{-} $, and $ K^{-}\pi^{+}e^{+}e^{-} $ using a 942 fb$^{-1}$ data set collected by the Belle detector at the KEKB…
We analyze the potential of rare charm decays as probes of new physics at a high-luminosity flavor facility operating at the $Z$ pole, such as the FCC-ee or CEPC. In particular, we identify clean null-test observables in $D^0 \to \pi^+…
The search for new physics beyond the standard model is proceeding nowadays intensively along experimental and theoretical lines. We review here the sector of charm radiative decays in this context. The calculation of $D\to V\gamma$, $D\to…
The LHCb bounds on the branching ratio of rare decay $D^0 \to \mu^+ \mu^-$ and the constraints on the branching ratio of $D^+ \to \pi^+ \mu^+ \mu^-$ in the nonresonant regions enable us to improve constraints on new physics contributions.…
We perform a global analysis of $|\Delta c| = |\Delta u| = 1$ transitions using recent data on $D^0 \to \mu^+\mu^-$, $D^+ \to \pi ^+\,\mu^+\mu^-$, $\Lambda_c \to p\,\mu^+\mu^-$, and $D^0 \to \pi^+\pi^-\,\mu^+\mu^-$ decays, and work out…
We analyze rare charm baryon decays within the standard model and beyond. We identify all null test observables in unpolarized $\Lambda_c \to p \ell^+ \ell^-$, $\ell=e, \mu$ decays, and study the new physics sensitivities. We find that the…
We present the first experimental search for the rare charm decay $D^{0} \to \pi^{0} \nu \bar{\nu}$. It is based on an $e^+e^-$ collision sample consisting of $10.6\times10^{6}$ pairs of $D^0\bar{D}^0$ mesons collected by the BESIII…