Search for $D^0 -> \ell^+\ell^-$ decays and for CP violation in $D^+_{(s)} \to K_S^0\pi^+$ and $D^+_{(s)} \to K_S^0K^+$ at BELLE

TL;DR

This paper reports on a comprehensive search for rare and forbidden charm meson decays, CP violation, and branching fractions using extensive data collected at the Belle detector, aiming to probe physics beyond the Standard Model.

Contribution

It presents new experimental searches for rare charm decays, CP violation, and branching fractions with the Belle detector, providing constraints on new physics models.

Findings

No evidence for $D^0 o ext{leptons}$ decays was observed.

Measured branching fractions for $D^+_{(s)}$ decays are consistent with previous results.

New limits on lepton-flavor violating decays were established.

Abstract

We are reporting on a search for flavour-changing neutral current decays $D^0 \to \mu^+ \mu^-$ and $D^0 \to e^+ e^-$, and for lepton-flavour violating decays $D^0 \to e^\pm \mu^\mp$, the measurement of $D^+_{(s)} \to K_S^0 \pi^+$ and $D^+_{(s)}\to K_S^0 K^+$ branching fractions, and the search for CP violation in $D^+_{(s)} \to K_S^0 \pi^+$ and $D^+_{(s)} \to K_S^0 K^+$ decays. The analyses are based on 600 fb$^{-1}$ to 700 fb$^{-1}$ of data collected in $e^+e^-$ collisions at the centre-of-mass (CM) energy of the $\Upsilon(4S)$ resonance and 60 MeV below by the Belle detector at the KEKB collider.