Related papers: Selecting the physical solution via $\eta$-$\eta'$…
Hadronic decay modes $D^0\to(\bar K^0, \bar K^{*0})\eta,\eta'$ and $(D^+,D_s^+)\to(\pi^+,\rho^+)\eta,\eta'$ are studied in the generalized factorization approach. Form factors for $(D,D_s^+)\to(\eta,\eta')$ transitions are carefully…
It is argued that the observed enhancement of the hadronic transition Upsilon(4S) -> Upsilon(1S) eta relative to Upsilon(4S) -> Upsilon(1S) pi pi can be explained if the resonance Upsilon(4S) contains an admixture of a four-quark component,…
We study the relation between the $\psi(4160)$ and the $Y(4260)$ within an unitarized effective Lagrangian approach. The $Y(4260)$ arises as a manifestation of the $\psi(4160)$, when a loop-driven decay of the type $\psi(4160)\to…
The triple-Pomeron coupling lies at the heart of the predictions for high energy diffractive processes. We explain why the existing determinations, which use single-particle inclusive hadronic data a+b -> a+Y, underestimate the value of the…
We study the decay process of $J/\psi\rightarrow e^+e^- \phi$ where the relatively clean electromagnetic (EM) transitions appear at leading order at tree level while the hadronic contributions only emerge via hadronic loop transitions. We…
The $\sigma$ resonance was observed as a conspicuous $\pi^+\pi^-$ peak in hadronic decays like $J/\psi\to \pi^+\pi^-\omega$ or $D^+\to\pi^+\pi^-\pi^+$. The phase of the $\sigma\to\pi^+\pi^-$ amplitude, extracted from production data within…
I introduce an entirely new dynamical description for exotic charmoniumlike hadrons, based upon the competing effects of the strong attraction between quarks in a diquark, and the inability of the diquark to hadronize on its own due to…
We have recently observed that hadron triangle singularities, that can mock new exotic hadrons, can be significanttly suppressed in relativistic heavy ion collisions, provided two conditions are met: these are, first, that the fireball…
We study the $D^+ \to \pi^+ \eta \eta $ and $D^+ \to \pi^+ \pi^0 \eta$ reactions, which are single Cabibbo suppressed and can proceed both through internal and external emission. The primary mechanisms at quark level are considered,…
A dispersive analysis of $\eta\to 3\pi$ decays has been performed in the past by many authors. The numerical analysis of the pertinent integral equations is hampered by two technical difficulties: i) The angular averages of the amplitudes…
I review recent insights and open questions connected with the production of eta--mesons from hadrons.
We perform a thorough analysis of the VP\gamma(\gamma*) and P\gamma\gamma(\gamma*) decays in the resonance chiral theory, where V stand for the vector resonances \rho, K*, \omega, \phi, P stand for \pi, K, \eta, \eta' and \gamma*…
This note describes the validation of material allowing the reinterpretation of an ATLAS search for decays of pair-produced neutral long-lived particles decaying in the hadronic part of the calorimeter, or at the edge of the electromagnetic…
A combined analysis of data on isoscalar S-wave processes $\pi\pi\to\pi\pi,K\overline{K},\eta\eta$ and on decays $J/\psi\to\phi\pi\pi,\phi K\overline{K}$ from the DM2, Mark III and BESIII collaborations is performed to study $f_0$ mesons.…
Hadronic resonances with short life times and strong coupling to the dense medium may exhibit mass shifts and width broadening as signatures of chiral symmetry restoration at the phase transition between hadronic and partonic matter.…
We study the three-body baryonic $B\to {\bf B\bar B'}M$ decays with $M$ representing the $\eta$ or $\eta'$ meson. Particularly, we predict that ${\cal B}(B^-\to\Lambda\bar p\eta,\Lambda\bar p\eta')=(5.3\pm 1.4,3.3\pm 0.7)\times 10^{-6}$ or…
Recent BESIII data on radiative $J/\psi$ decays from $\sim 10^{10}$ $J/\psi$ samples should significantly advance our understanding of the controversial nature of $\eta(1405/1475)$. This motivates us to develop a three-body unitary…
The recent multiple-solution problem in extracting physics information from a fit to the experimental data in high energy physics is reviewed in a mathematical viewpoint. All these multiple solutions were found via a fit process previously,…
The suitability of using non-relativistic quantum mechanics to investigate heavy quark mesons is illustrated through a study of the charmonium meson. We consider a limiting form of the QCD potential which is a simple combination of the…
In this paper, we take into account the intrinsic charm and gluonic contents into the $\eta-\eta^\prime$ mixing scheme and formulate the tetramixing $\eta-\eta^\prime-G-\eta_c$ to study the mixing properties of $\eta^{(\prime)}$ mesons.…