Charm physics, which involves a heavy up-type quark, offers a unique environment in which to search for new particles and couplings beyond the Standard Model. Studies with charmed hadron decays complement those in B physics, expanding the potential to observe BSM phenomena. The Belle II experiment has an active charm physics program that includes studies of rare decays, CP violation, flavor...

The strong and electromagnetic interactions are two main decay mechanisms

in charmonium decays. The relative phase between them is a basic parameter in understanding the

decay dynamics, especially for the precise measurements. Based on indirect studies on Jpsi two body

decay modes: 1-0-, 0-0-, 1-1-, and NNbar, the relative phase is around 90 degrees. There is also some results from...

In this talk, based on the work [PRD109,054008], we develop a model aimed at understanding the three mass distributions of pairs of mesons in the Cabibbo-suppressed $D^+_s \to K^+ \pi^+ \pi^-$ decay recently measured with high statistics by the BESIII collaboration. The largest contributions come from the $\rho^0$ and $K^{*0}$ related decay modes, but the $K^*_0(1430)$ and $f_0(1370)$ modes...

We study the J/ψ → ϕπ+a0(980),(a0 → π−η) decay, evaluating the double mass distribution in terms of the π−η and π+a0 invariant masses. We show that the π−η mass distribution exhibitsthe typical cusp structure of the a0(980) seen in recent high statistics experiments, and the π+a0

spectrum shows clearly a peak around Minv(π+a0) = 1420 MeV, corresponding to a triangle singularity. When...

The system of η and η′ offers a flavor-conserving laboratory to test the low-energy QCD and to search for new physics Beyond the Standard Model. The symmetry properties of QCD at low-energy, such as the chiral symmetry or the axial anomalies, are manifested in the decays of η and η′. Thus, a study of $\eta^{(\prime)}$ will yield light on our understanding of the origin and the dynamics of QCD...

The electromagnetic form factor of the charged pion encodes relevant information in hadron dynamics. On the one hand, its phase is related (modulo isospin-breaking corrections) to the universal $\pi\pi$ $P$-wave phase shift, that appears in a variety of hadronic processes. On the other hand, it appears as an essential input to describe hadronic electromagnetic interactions when employing...

The sensitivity of the rare decays $\eta\to\pi^{0}\gamma\gamma$ and

$\phi\to\pi^{0}\eta\gamma$ to signatures of a leptophobic $B$ boson in the MeV-GeV mass range is analyzed in this talk.

By adding an explicit $B$-boson resonance exchange to the Standard Model contributions from vector and scalar meson exchanges,

and employing experimental data for the associated branching ratios

and...

This abstract presents a thorough analysis of the φ → 3π decay amplitude, including a study of its behavior using different phase shift parametrizations. Based on recent experimental results, we delve into the intricacies of this decay process and also explore the φπ0 transition form factor. By employing the Khuri–Treiman equations approach, we establish a strong agreement between the...

The $D^{+} \to K_s^0 \pi^{+} \eta$ reaction was recently measured by the BESIII collaboration [1]. The reaction is actually $D^{+} \to \bar{K}^0 \pi^{+} \eta$, with the $\bar{K}^0$ observed as a $K_s^0$ state.

We study the $D^{+} \to \bar{K}^0 \pi^{+} \eta$ reaction, where the $a_0(980)$ excitation plays a dominant role. We consider mechanisms of external and internal emission at the quark...