arXiv subjects

Zong-Ye Zhang

Publications and source records attributed to Zong-Ye Zhang.

8 recordsLinked to original sources

arXiv2024

Reveal short range interactions between $u/d$ quarks in the $NN$, $D_{03}$, and $D_{30}$ systems

The dynamic mechanism of short range interactions between $u/d$ quarks remains an open and challenging problem. In order to reveal this quark dynamics, we perform a systematic analysis of $NN$, $D_{03}$, and $D_{30}$ systems in the (extended) chiral SU(3) constituent quark models. By comparing results calculated with different models and different parameter sets, the effects of one gluon exchange and vector meson exchange terms are carefully examined. The results indicate that the vector meson exchange interactions dominate the short range interactions between $u/d$ quarks, whereas the small residual one gluon exchange coupling strength is also allowed.

hep-ph↗

arXiv2018

The opportunity to find $\bar{d}^\ast(2380)$ in the $Υ(nS)$ decay

$d^\ast(2380)$ was observed by WASA-at-COSY collaborations in the nuclear reaction recently. Its particularly narrow width may indicate the new QCD-allowed hadronic structure. To further confirm the existence of this peculiar particle in a totally different kind of reaction, we study the opportunity for searching $\bar{d}^\ast$ in the $Υ(nS)$ (with n=1, 2, 3) decay. As a phenomenological study, our framework is based on SU(3) chiral quark model. By virtue of the unitarity of $S$-matrix and crossing symmetry, we study the imaginary part of the forward scattering amplitudes between $Υ(nS)$ and $d^\ast$. The scattering process is mainly governed by the quark-meson interaction. We examine both the pseudoscalar and vector meson contribution in the intermediate state. Hopefully, our results show that it's quite possible to find $\bar{d}^\ast$ in this decay mode in the future.

hep-ph↗

arXiv2016

Properties of single cluster structure of $d^*(2380)$ in chiral SU(3) quark model

The structure of $d^*(2380)$ is re-studied with the single cluster structure in the chiral SU(3) quark model which has successfully been employed to explain the scattering and binding behaviors of baryonic systems. The mass and width are explicitly calculated with two types of trial wave functions. The result shows that the $(0s)^6 [6]_{orb}$ configuration is easy to convert to the configuration with the same $[6]_{orb}$ symmetry but $2\hbar ω$ excitation back and forth, however, it is seldom to turn into a two-cluster configuration with a (1s) relative motion in between. The resultant mass and width are about $2394$MeV and $25$MeV, respectively, and the stable size is about $0.75fm$, which are consistent with both the results in the two-cluster configuration calculation and the data measured by the COSY collaboration. It seems that the observed $d^*$ is a six-quark dominated exotic state with a spherical shape and breath mode in the coordinate space. Moreover, if $d^*$ does have $2\hbar ω$ excitation, the $d^* \to npπππ$ decay mode might be a good place to distinguish the real structure of the observed phenomenon by COSY. The masses of various isospin-spin states of six-light-quark systems are also computed. It is shown that by considering the coupling with the configurations with $2\hbar ω$ excitations, only the mirror state with $IS$=$30$ will be lower down to the place where whose mass is slightly higher than the value of the $ΔΔ$ threshold.

hep-ph↗

arXiv2013

A Study of P-wave Heavy Meson Interactions in A Chiral Quark Model

The analytical forms of the interaction potentials between one S-wave and one P-wave heavy mesons as well as the potentials between two P-wave heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive property between two heavy mesons. Consequently, a series of possible molecular states are obtained. It is expected that our study might shed some light on the popular discussions of the newly observed XYZ states.

nucl-th↗

arXiv2010

A study of meson-meson potential in the chiral quark model

An effective potential in a meson-meson system is discussed based on the SU(3) chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is employed to study the bound state problem of $ωϕ$, which is related to the new resonance of $f_0(1810)$ observed in BESII very recently.

hep-ph↗

arXiv2009

A chiral quark model study of $Z^+(4430)$ in the molecular picture

We investigated the bound state problem of the S wave charged $D_1 \bar{D}^*$ ($D_1' \bar{D}^*$) system in a chiral quark model by solving the resonating group method equation. Our preliminary study does not favor the molecular assumption of $Z^+(4430)$. On the contrary, if $Z^+(4430)$ is really a molecule, its partner with opposite $G$-parity should also exist and probably may be found in the $π^+η_c(2S)$, $J/ψπ^+π^0$, or $ψ'π^+π^0$ channel. For the bottom systems, we found the existence of both $I^G$=$1^+$ and $I^G$=$1^-$ $B_1 \bar{B}^*$ ($B_1' \bar{B}^*$) molecules is possible.

hep-ph↗

arXiv2009

The bound state problem of S-wave heavy quark meson-aitimeson systems

We investigated systematically whether the S-wave ($\bar{Q}q$) meson and the ($Q\bar{q}$) meson may form S-wave bound states in a chiral SU(3) quark model by solving the resonating group method equation. Here $Q=c$ or $b$ and $q=u$, $d$ or $s$. Our preliminary calculation disfavors the existence of $I=\frac12$ ($\bar{Q}l$)-($Q\bar{s}$) molecules ($l=u,d$) while favors the existence of isoscalar $B\bar{B}$, $B^*\bar{B}^*$ (J=2) and $B\bar{B}^*$ (C=+) molecules. The existence of isovector (charm-anticharm) and (charm-bottom) molecules is also disfavored. Therefore the resonance-like structure $Z^+(4051)$ is unlikely to be an S-wave $D^*\bar{D}^*$ molecule.

hep-ph↗

arXiv2009

X(3872) and the bound state problem of $D^0\bar{D}^{\ast0}$ ($\bar{D}^0{D}^{\ast0}$) in a chiral quark model

The bound state problem of $D^0\bar{D}^{\ast0}$ ($\bar{D}^0{D}^{\ast0}$) is relevant to the molecular interpretation of the X(3872). We investigated this problem in a chiral quark model by solving the resonating group method equation. We found the system is unbound through S-wave $π$ and $σ$ interactions. The inclusion of $ρ$ and $ω$ meson exchanges is helpful to the formation of a molecule. Because the binding energy relies on the coupling constants, we cannot draw a definite conclusion whether a molecular state exists in $D^0\bar{D}^{\ast0}$ ($\bar{D}^0{D}^{\ast0}$) system. When moving on to the bottom counterpart, we obtained an S-wave $B\bar{B}^\ast$ state.

hep-ph↗