Related papers: Decay channels and charmonium mass-shifts
We determine the radiative decay amplitudes for decay into $D^*$ and $\bar{D} \gamma$, or $D^*_s$ and $\bar{D}_s \gamma$ of some of the charmonium like states classified as X,Y,Z resonances, plus some other hidden charm states which are…
We investigate the mass spectrum and electromagnetic processes of charmonium system with the nonperturbative treatment for the spin-dependent potentials, comparing the pure scalar and scalar-vector mixing linear confining potentials. It is…
Through the spin rearrangement scheme in the heavy quark limit, we have performed a comprehensive investigation of the decay pattern and production mechanism of the hidden beauty di-meson states, which are either composed of a P-wave bottom…
Coupled-channel effects due to coupling of charmonia to the charmed and anticharmed mesons are of current interest in heavy quarkonium physics. However, the effects have not been unambiguously established. In this paper, a clean method is…
Although the spectra of heavy quarkonium systems have been successfully explained by certain QCD motivated potential models, their strong decays are still an open problem. We perform a microscopic calculation of vector charmonium strong…
Charmonium states can decay into pairs of $D$ and $\overline{D}$ mesons if their masses are above the allowed decay thresholds. In general $c\bar{c}$ states near threshold will also undergo mixing with $D\overline{D}$ molecular (or…
A large number of new states have been reported during the last few years in charmonium spectroscopy above the charmed meson production threshold. They have been called $X's$, $Y's$, and $Z's$. We reflect on the influence of thresholds on…
The charmonium spectrum is calculated with two nonrelativistic quark models, the linear potential model and the screened potential model. Using the obtained wavefunctions, we evaluate the electromagnetic transitions of charmonium states up…
We present a selection of recent results from the BESIII collaboration, including both charmonium and $D$ meson physics. We first discuss the observation of a charged, charmonium-like state, the $Z_c(3900)$. Conventional charmonium topics…
In this work, we investigate the mass spectra of excited charmonia employing a nonrelativistic potential model with screening effect, and analyze their two-body strong decay, two-photon decay, leptonic decay, and hadronic transitions.…
The relativistic four-quark equations with the open-charm and the open-strange are found in the framework of coupled-channel formalism. The dynamical mixing of the meson-meson states with the four-quark states is considered. The four-quark…
This note introduces a family of circulant quantum channels -- a subclass of the mixed-permutation channels -- and investigates its key structural and operational properties. We show that the image of the circulant quantum channel is…
Using the QCD sum rule approach we study the X(4260) state assuming that it can be described by a mixed charmonium-tetraquark current with $J^{PC}=1^{--}$ quantum numbers. For the mixing angle around $\theta=(53.0 \pm 0.5)^0$, we obtain a…
We present results for chiral extrapolations of the mass and decay constants of the rho meson. The data sets used are the nf=2 unquenched gauge configurations generated with twisted mass fermions by the European Twisted Mass Collaboration.…
A review of recent experimental developments concerning the $X$, $Y$ and $Z$ charmonium-like exotic states.
A simple method is proposed for determining the masses of new particles in collider events containing a pair of decay chains (not necessarily identical) of the form Z -> Y+1, Y -> X+2, X -> N+3, where 1,2 and 3 are visible but N is not.…
While many properties of the vector charmonium first excitations are yet to be measured, enhancements at unexpected energies are intriguing, alias the $Y$ states. In order to understand the naturally unquenched mesonic line-shapes, the…
An interesting controversy has emerged challenging the widely accepted nature of the $X(3915)$ and the $X(3930)$ resonances, which had initially been assigned to the $\chi_{c0}(2P)$ and $\chi_{c2}(2P)$ $c\bar c$ states, respectively. To…
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 investigate $2P$-$1F$ mixing in charmonium, focusing on the close-in-mass $\chi_{c2}(2P)$ and $\chi_{c2}(1F)$ states. The conventional tensor force yields negligible mixing, motivating the inclusion of coupled-channel effects. Our…