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In this work, we systematically calculate the spectrum of hidden-charm pentaquark states $qqqc\bar{c}$ $(q = u,d)$ in the chiral SU(3) quark model, which has been quite successful in reproducing consistently the energies of octet and decuplet baryon ground states, the binding energy of deuteron, and the nucleon-nucleon ($NN$) scattering phase shifts and mixing parameters for partial waves with total angular momentum up to $J=6$. The Hamiltonian contains the one-gluon-exchange (OGE) potential, the Goldstone-boson-exchange (GBE) potential, the confinement potential, and the kinetic energy of the system. We solve the Schr\"odinger equation by use of the variational method. It is found that the masses of all the experimentally observed $P_c(4312)$, $P_c(4380)$, $P_c(4440)$, and $P_c(4457)$ states are much overestimated, indicating that these states are not compact pentaquark states in the chiral SU(3) quark model. All other $qqqc\bar{c}$ $(q = u,d)$ states are found to lie much above the corresponding baryon-meson thresholds, and thus are not suggested as stable pentaquark states due to their fall-apart decays. A detailed comparison of the results with those obtained in the OGE model and the chromomagnetic interaction (CMI) model is further given., Comment: 9 pages, 1 figure. arXiv admin note: substantial text overlap with arXiv:2403.15187

Inspired by the resonance $T_{cc}^+(3875)$ recently observed by the LHCb Collaboration, we systematically explore the $S$- and $P$-wave $cc\bar{q}\bar{q}'$ $(\bar{q},\bar{q}' = \bar{u}, \bar{d}, \bar{s})$ systems in a chiral SU(3) quark model. The Hamiltonian contains the kinetic energy, the one-gluon-exchange (OGE) potential, the confinement potential, and the one-boson-exchange (OBE) potential stemming from the coupling of quark and chiral fields. The Schr\"odinger equation is solved by use of the variational method with the spacial trial wave functions chosen as Gaussian functions. It is found that the lowest state has a mass $3879$ MeV, isospin and spin-parity $IJ^P=01^+$, and quark constituent $cc\bar{u}\bar{d}$, in agreement with the experimentally observed $T_{cc}^+(3875)$. This state is approximately at the calculated $DD^\ast$ threshold, and has a root-mean-square radius about $0.48$ fm. These demonstrates that the $T_{cc}^+(3875)$ can be accommodated as a stable and compact tetraquark sate in the chiral SU(3) quark model. All the other $S$- and $P$-wave $cc\bar{q}\bar{q}'$ $(\bar{q},\bar{q}' = \bar{u}, \bar{d}, \bar{s})$ states lie about one hundred to few hundreds MeV higher than the corresponding meson-meson thresholds, and thus are not suggested to be candidates of stable and compact tetraquark states due to their fall-apart decays to two mesons., Comment: 9 pages, 2 figures

The mass spectrum of hidden charm pentaquark states composed of two diquarks and an antiquark are calculated by use of an effective Hamiltonian which includes explicitly the spin, color, and flavor dependent interactions. The results show that the $P_c(4312)^+$ and $P_c(4440)^+$ states could be explained as hidden charm pentaquark states with isospin and spin-parity $IJ^P=1/2\left(3/2^-\right)$, the $P_c(4457)^+$ state could be explained as a hidden charm pentaquark state with $IJ^P=1/2\left(5/2^-\right)$, and the $P_{cs}(4459)^+$ state could be explained as a hidden charm pentaquark state with $IJ^P=0\left(1/2^-\right)$ or $0\left(3/2^-\right)$. Predications for the masses of other possible pentaquark states are also given, and the possible decay channels of these hidden charm pentaquark states are discussed., Comment: 9 pages

The purpose of the present study is to explore the mass spectrum of the hidden charm tetraquark states within a diquark model. Proposing that a tetraquark state is composed of a diquark and an antidiquark, the masses of all possible $[qc][\bar{q}\bar{c}]$, $[sc][\bar{s}\bar{c}]$, and $[qc][\bar{s}\bar{c}]$ $\left([sc][\bar{q}\bar{c}]\right)$ hidden charm tetraquark states are systematically calculated by use of an effective Hamiltonian, which contains color, spin, and flavor dependent interactions. Apart from the $X(3872)$, $Z(3900)$, $\chi_{c2}(3930)$, and $X(4350)$ which are taken as input to fix the model parameters, the calculated results support that the $\chi_{c0}(3860)$, $X(4020)$, $X(4050)$ are $[qc][\bar{q}\bar{c}]$ states with $I^GJ^{PC}=0^+0^{++}$, $1^+1^{+-}$, and $1^-2^{++}$, respectively, the $\chi_{c1}(4274)$ is an $[sc][\bar{s}\bar{c}]$ state with $I^GJ^{PC}=0^+1^{++}$, the $X(3940)$ is a $[qc][\bar{q}\bar{c}]$ state with $I^GJ^{PC}=1^-0^{++}$ or $1^-1^{++}$, the $Z_{cs}(3985)^-$ is an $[sc][\bar{q}\bar{c}]$ state with $J^{P}=0^{+}$ or $1^+$, and the $Z_{cs}(4000)^+$ and $Z_{cs}(4220)^+$ are $[qc][\bar{s}\bar{c}]$ states with $J^{P}=1^{+}$. Predictions for other possible tetraquark states are also given., Comment: 9 pages. Version published in Phys. Rev. D

Both unitary chiral theories and lattice QCD simulations show that the $DK$ interaction is attractive and can form a bound state, namely, $D^*_{s0}(2317)$. Assuming the validity of the heavy antiquark-diquark symmetry (HADS), the $\Xi_{cc}\bar{K}$ interaction is the same as the $DK$ interaction, which implies the existence of a $\Xi_{cc}\bar{K}$ bound state with a binding energy of $49-64$ MeV. In this work, we study whether a $\Xi_{cc}\Xi_{cc}\bar{K}$ three-body system binds. The $\Xi_{cc}\Xi_{cc}$ interaction is described by exchanging $\pi$, $\sigma$, $\rho$, and $\omega$ mesons, with the corresponding couplings related to those of the $NN$ interaction via the quark model. We indeed find a $\Xi_{cc}\Xi_{cc}\bar{K}$ bound state, with quantum numbers $J^P=0^-$, $I=\frac{1}{2}$, $S=1$ and $C=4$, and a binding energy of $80-118$ MeV. It is interesting to note that this system is very similar to the well-known $NN\bar{K}$ system, which has been studied extensively both theoretically and experimentally. Within the same framework, we show the existence of a $NN\bar{K}$ state with a binding energy of $35-43$ MeV, consistent with the results of other theoretical works and experimental data, which serves as a consistency check on the predicted $\Xi_{cc}\Xi_{cc}\bar{K}$ bound state., Comment: 12 pages, 2 figures

The photoproduction of $\gamma p \to K^+ \Sigma^0(1385)$ is investigated based on an effective Lagrangian approach using the tree-level Born approximation, with the purpose of understanding the reaction mechanisms and resonance contents and their associated parameters in this reaction. In addition to the $t$-channel $K$ and $K^\ast(892)$ exchanges, $s$-channel nucleon ($N$) exchange, $u$-channel $\Lambda$ exchange, and generalized contact term, the exchanges of a minimum number of $N$ and $\Delta$ resonances in the $s$ channel are taken into account in constructing the reaction amplitudes to describe the experimental data. It is found that the most recent differential cross-section data from the CLAS Collaboration can be well reproduced by including one of the $N(1895){1/2}^-$, $\Delta(1900){1/2}^-$, and $\Delta(1930){5/2}^-$ resonances. The reaction mechanisms of $\gamma p \to K^+ \Sigma^0(1385)$ are discussed in detail, and the predictions of the beam and target asymmetries for this reaction are given. The cross sections of $\gamma p \to K^0 \Sigma^+(1385)$ are shown to be able to further constrain the theoretical models and pin down the resonance contents for $\gamma p \to K^+ \Sigma^0(1385)$., Comment: 11 pages, 9 figures. Version published in PRD. arXiv admin note: text overlap with arXiv:1704.04562, arXiv:1810.07012

The purpose of the present study was to explore the possibility of accommodating the $d^*(2380)$ and its flavor SU(3) partners in a diquark model. Proposing that $d^*(2380)$ is composed of three vector diquarks, its mass is calculated by use of an effective Hamiltonian approach and its decay width is estimated by considering the effects of quark tunneling from one diquark to the others and the decays of the subsequent two-baryon bound state. Both the obtained mass and decay width of $d^*(2380)$ are in agreement with the experimental data, with the unexpected narrow decay width being naturally explained by the large tunneling suppression of a quark between a pair of diquarks. The masses and decay widths of the flavor SU(3) partners of $d^*(2380)$ are also predicated within the same diquark scenario., Comment: 5 pages, 1 figure

The high-precision differential cross-section data for the reaction $\gamma p \to K^{*+}\Lambda$ are reanalyzed within a Regge-inspired effective Lagrangian approach. The model adopts Regge phenomenology to constrain the $t$-channel contributions from the $\kappa$, $K$, and $K^*$ exchanges. A minimal number of resonances in the $s$ channel are introduced in constructing the reaction amplitudes in order to describe the data. It is shown that the differential cross-section data for $\gamma p \to K^{*+}\Lambda$ can be satisfactorily described by introducing the only $N(2060){5/2}^-$ resonance in the $s$ channel, which is quite different from our earlier work performed in an effective Lagrangian approach [A. C. Wang {\it et al.}, Phys. Rev. C 96, 035206 (2017)], where the amplitudes are computed by evaluating Feynman diagrams and it is found that introducing at least one additional resonance apart from the $N(2060){5/2}^-$ is indispensable for reproducing the data. The roles of individual contributions from meson and baryon exchanges on the angular distributions are found to be highly model dependent. The extracted mass of $N(2060){5/2}^-$ turns out to be well determined, independent of how the $t$-channel amplitudes are constructed, whereas the width does not., Comment: 10 pages, 5 figures, version published in PRC

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., Comment: arXiv admin note: substantial text overlap with arXiv:1206.0523

Enrichment is one of the important educational models for gifted students. However, the research on gifted enrichment programs rarely leads to instructional interventions for culturally diverse students. The purposes of this study were: (a) to propose an ecology enrichment summer program for gifted students from mainstream and diverse cultural backgrounds, and (b) to investigate the learning effects of this enrichment program on the multicultural groups. The participants consisted of 31 elementary intellectually gifted students from Jungli city (urban), rural area, and aboriginal tribes in Taoyuan County, Taiwan. The 3-day enrichment program focused on role models, social interaction, brainstorming, multicultural atmosphere, and adding multi-sensory learning of ecology that could expand the regular curriculum in school. Data analysis used in this study included the repeated-measures t-tests and analysis of covariance. The results indicated that overall participants' knowledge on ecology improved significantly after the enrichment activities. Likewise, there were significant knowledge differences between pre- and posttest scores for the three groups. Nevertheless, no significant difference in knowledge performance was found regardless of the status of cultural background. In addition, interview data revealed that mainstream students gained more multicultural experiences while culturally diverse students increased awareness of their culture. (Contains 4 tables.) [This paper was published in: C. C. Kuo, L. W. Chang, C. Y. Chen, I. M. Li, H. F. Chen, P. J. Chou, Y. C. Wang, K. S. Chen, H. J. Chang, & W. K. Chen (Eds.), Meeting Unique Needs of the Gifted: Proceedings of the 9th Asia-Pacific Conference on Giftedness (pp.263-272). Taipei: National Taiwan Normal University.]

Previous findings have indicated that the reasoning abilities of gifted students are associated with gender differences. However, the factors affecting the emergence of gender differences, including age, remain to be studied. The main purpose of this study is to investigate whether the spatial, verbal and quantitative reasoning abilities of gifted children exhibit gender differences prior to entering elementary school. A sample of 32 young children identified as academically gifted were administered individual intelligence tests in order to find out their verbal and spatial IQ scores, as well as their arithmetic scores. The mean performance of these male and female young gifted children on three reasoning measures showed that gender differences were not significantly different. Means across sub-skills however, revealed that boys scored higher than girls on tasks in which assembly and number series abilities were required. (Contains 1 table.)