arXiv subjects

Bing-Ran He

Publications and source records attributed to Bing-Ran He.

12 recordsLinked to original sources

arXiv2023

Ground states of all mesons and baryons in a quark model with Hidden Local Symmetry

We extend the chiral quark model for $u$, $d$, $c$ and $b$ quarks with vector mesons, which we proposed in the previous analysis, to a model with the $s$ quark. We include the nonet pseudo-scalar and vector mesons together with the singlet scalar meson based on the SU(3)$_L \times$SU(3)$_R$ chiral symmetry combined with the Hidden Local Symmetry, which mediate force among $u$, $d$ and $s$ quarks. We fit the model parameters to the known ground state mesons and baryons. We show that the mass spectra of those hadrons are beautifully reproduced. We predict the masses of missing ground states, one meson and twenty baryons, which will be tested in the future experiment.

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arXiv2023

Quark model with Hidden Local Symmetry and its application to $T_{cc}$

We propose a chiral quark model including the $\omega$ and $\rho$ meson contributions in addition to the $\pi$ and $\sigma$ meson contributions. We show that the masses of the ground state baryons such as the nucleon, $\Lambda_c$ and $\Lambda_b$ are dramatically improved in the model with the vector mesons compared with the one without them. The study of the tetraquark $T_{cc}$ is also performed in a coupled channel calculation and the resultant mass is much closer to its experimental value than the result without vector meson contribution. This approach can be applied to the future study of multi-quark systems.

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arXiv2022

Investigating full-heavy tetraquarks composed of $cc\bar{c}\bar{b}$ and $bb\bar{b}\bar{c}$

The full-heavy tetraquarks $cc\bar{c}\bar{b}$ and $bb\bar{b}\bar{c}$ are systematically investigated within the chiral quark model. The meson-meson structure, diquark-antidiquark structure and K-structure are considered in this work. There is no bound state for $cc\bar{c}\bar{b}$ and $bb\bar{b}\bar{c}$ systems in $ IJ^{P}=00^{+},01^{+}$ and $ 02^{+}$ channels. However, for $cc\bar{c}\bar{b}$ system, three possible resonance states with energy of $ 10079~{\rm MeV} $, $ 10081~{\rm MeV} $ and $ 10177~{\rm MeV} $ are found in $ IJ^{P}=00^{+},01^{+}$ and $ 02^{+}$, respectively, and their decay width $ \Gamma$ are $6.7-8.4~{\rm MeV} $, $1.4-7.2~{\rm MeV} $ and $9.1-11.1~{\rm MeV} $. For $bb\bar{b}\bar{c}$ system, there also exist three possible resonance states with energy of $ 16474~{\rm MeV} $, $ 16474~{\rm MeV} $ and $ 16541~{\rm MeV} $ in $ IJ^{P}=00^{+},01^{+}$ and $ 02^{+}$, respectively, and the decay widths $ \Gamma$ of them are $2.2-6.1~{\rm MeV} $, $2.2-6.9~{\rm MeV} $ and $5.3-8.5~{\rm MeV} $. $bc\bar{c}\bar{c}$ and $cb\bar{b}\bar{b}$ systems will have the same results as $cc\bar{c}\bar{b}$ and $bb\bar{b}\bar{c}$, respectively. These full-heavy resonance states are worthy to be searched in the future experiments.

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arXiv2020

Study of $qqq\bar{q}Q$ pentaquark system in the Chiral Quark Model

With the discovery of some hidden-charm pentaquark resonances by the LHCb Collaboration, investigations of pentaquark states containing heavy quarks have aroused the interest of theorists. We study herein $qqq\bar{q}Q$ ($q = u$ or $d$, $Q=c$ or $b$) pentaquark system, in the framework of the chiral quark model. In consequence, some charmed and bottomed pentaquarks are considered to exist by five-body dynamical calculations. In the charm sector, $\Sigma_c\pi(IJ^P=0\frac{1}{2}^-)$ and $\Sigma_c^*\pi(IJ^P=0\frac{3}{2}^-)$ are possible candidates of $\Lambda_c(2595)$ and $\Lambda_c(2625)$, respectively. Besides, two high-spin states, $\Sigma_c^*\rho(IJ^P=0\frac{5}{2}^-)$ and $\Delta D^*(IJ^P=1\frac{5}{2}^-)$, are also found in the energy region of $3.2 \sim 3.3$ GeV. In the bottom sector, $\Sigma_b\pi(IJ^P=0\frac{1}{2}^-)$, $\Sigma_b^*\pi(IJ^P=0\frac{3}{2}^-)$ could be candidates of $\Lambda_b(5912)$ and $\Lambda_b(5920)$, respectively. And $\Sigma_b^*\rho(IJ^P=0\frac{5}{2}^-)$ and $\Delta B^*(IJ^P=1\frac{5}{2}^-)$ are found in the energy region of $6.5 \sim 6.6$ GeV. $\Sigma_c^{(*)}\pi$ and $\Sigma_b^{(*)}\pi$ are expected as compact states, while $\Sigma_c^*\rho$, $\Sigma_b^*\rho$, $\Delta D^*$ and $\Delta B^*$ are expected as molecular states.

hep-ph↗

arXiv2020

Pentaquarks with the $qqs\bar{Q}Q$ configuration in the Chiral Quark Model

We study the five-quark system composed of $qqs\bar{Q}Q$ configuration ($q = u$ or $d$, $Q=b$ or $c$), in the framework of the chiral quark model. In consequence, a series of bound states with heavy flavors are predicted by precise five-body dynamical calculations. We found that taking color-octet structure into consideration always provides more bounding energy than color-singlet structure, and the more heavier quark prevents, the easier to form the bound states. We suggest $qqs\bar{b}b$ configuration is a compact $\bar{b}b$-pair surrounded by three other quarks, while $qqs\bar{b}c$, $qqs\bar{c}b$ and $qqs\bar{c}c$ configurations are molecular states.

hep-ph↗

arXiv2018

Magnetic field dependence of Delta isobars properties in a Skyrme model

The properties of $\Delta$ isobars in a uniform magnetic field are investigated. In the weak magnetic field region, the general relations between magnetic moment of nucleons and $\Delta$ isobars are given. In the strong magnetic field region, the mass and size of $\Delta$ isobars depend on the increasing of magnetic field strength in different ways: the effective mass of $\Delta^{++}$, $\Delta^{+}$ and $\Delta^{0}$ first decreases and then increases, consequently, the size of $\Delta^{++}$, $\Delta^{+}$ and $\Delta^{0}$ first increases and then decreases; whereas, the effective mass of $\Delta^{-}$ always increases, and consequently, the size of $\Delta^{-}$ always decreases. The estimation shows in the core part of the magnetar, the equation of state for $\Delta$ isobars depends on the magnetic field, which affects the mass limit of the magnetar.

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arXiv2016

Skyrme model study of proton and neutron properties in a strong magnetic field

The proton and neutron properties in a uniform magnetic field are investigated. The Gell-Mann-Nishijima formula is shown to be satisfied for baryon states. It is found that with increasing magnetic field strength, the proton mass first decreases and then increases, while the neutron mass always increases. The ratio between magnetic moment of proton and neutron increases with the increase of the magnetic field strength. With increasing magnetic field strength, the size of proton first increases and then decreases, while the size of neutron always decreases. The present analyse implies that in the core part of the magnetar, the equation of state depend on the magnetic field, which modifies the mass limit of the magnetar.

hep-ph↗

arXiv2015

Magnetic response of baryon properties in a skyrmion model

An axially symmetric ansatz is proposed to investigate the properties of baryon in a uniform magnetic field. The baryon number is shown to be conserved, while the baryon shape is stretched along the magnetic field. It is found that with increasing magnetic field strength, the static mass of the baryon first decreases and then increases, while the size of the baryon first increases and then decreases. Finally, in the core part of the magnetar, the equation of state strongly depends on the magnetic field, which modifies the mass limit of the magnetar.

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arXiv2015

Effects of scalar mesons in a Skyrme model with hidden local symmetry

We study the effects of light scalar mesons on the skyrmion properties by constructing and examining a mesonic model including pion, rho meson, and omega meson fields as well as two-quark and four-quark scalar meson fields. In our model, the physical scalar mesons are defined as mixing states of the two- and four-quark fields. We first omit the four-quark scalar meson field from the model and find that when there is no direct coupling between the two-quark scalar meson and the vector mesons, the soliton mass is smaller and the soliton size is larger for lighter scalar mesons; when direct coupling is switched on, as the coupling strength increases, the soliton becomes heavy, and the radius of the baryon number density becomes large, as the repulsive force arising from the $\omega$ meson becomes strong. We then include the four-quark scalar meson field in the model and find that mixing between the two-quark and four-quark components of the scalar meson fields also affects the properties of the soliton. When the two-quark component of the lighter scalar meson is increased, the soliton mass decreases and the soliton size increases.

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arXiv2014

Mass degeneracy of the heavy-light mesons with chiral partner structure in the half-skyrmion phase

We explore the mass splitting of the heavy-light mesons with chiral partner structure in nuclear matter. In our calculation, we employed the heavy hadron chiral perturbation theory with chiral partner structure and the nuclear matter is constructed by putting skyrmions from the standard Skyrme model onto the face-centered cubic crystal and regarding the skyrmion matter as nuclear matter. We find that, although the masses of the heavy-light mesons with chiral partner structure are splitted in the matter-free space and skyrmion phase, they are degenerated in the half-skyrmion phase in which the chiral symmetry is restored globally. This observation suggests that the magnitude of the mass splitting of the heavy-light mesons with chiral partner structure can be used as a probe of the phase structure of the nuclear matter.

hep-ph↗

arXiv2014

$D$ and $D^{\ast}$ meson mixing in spin-isospin correlated cold nuclear matter

We propose to study the mass spectrum of the heavy-light mesons to probe the structure of the spin-isospin correlation in the nuclear medium. We point out that the spin-isospin correlation in the nuclear medium generates a mixing among the heavy-light mesons carrying different spins and isospins such as $D^+$, $D^0$, $D^{\ast +}$, and $D^{\ast 0}$ mesons. We use two types of correlations motivated by the skyrmion crystal and the chiral density wave as typical examples to obtain the mass splitting caused by the mixing. Our result shows that the structure of the mixing reflects the pattern of the correlation, i.e., the remaining symmetry. Furthermore, the magnitude of the mass modification provides information of the strength of the correlation.

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arXiv2013

Parity doubling structure of nucleon at non-zero density in the holographic mean field theory

We develope the holographic mean field theory approach in a bottom-up holographic QCD model including baryons and scalar mesons in addition to vector mesons and pions. We study the effect of parity doubling structure of baryons at non-zero density to the equation of state between the chemical potential and the baryon number density. We first show that we can adjust the amount of nucleon mass coming from the chiral symmetry breaking by changing the boundary value of the five-dimensional baryon fields. Then, introducing the mean field for the baryon fields, we calculate the equation of state between the baryon number density and its corresponding chemical potential. Then, comparing the predicted equation of state with the one obtained in a Walecka type model, we extract the density dependence of the effective nucleon mass. The result shows that the effective mass decreases with increasing density, and that the rate of decreasing is more rapid for the larger percentage of the mass coming from the chiral symmetry breaking.

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