Analysis of the X(1576) as a tetraquark state with the QCD sum rules

In this letter, we take the point of view that the X(1576) be tetraquark state which consists of a scalar-diquark and an anti-scalar-diquark in relative $P$-wave, and calculate its mass in the framework of the QCD sum rules approach. The numerical value of the mass $m_X=(1.66\pm 0.14) GeV$ is consistent with the experimental data, there may be some tetraquark component in the vector meson X(1576).Comment: 6 pages, 1 figure, second version, typos correcte

Analysis of the vertex D∗D∗ρD^*D^* \rho with the light-cone QCD sum rules

In this article, we analyze the vertex $D^*D^*\rho$ with the light-cone QCD sum rules. The strong coupling constant $g_{D^*D^*\rho}$ is an important parameter in evaluating the charmonium absorption cross sections in searching for the quark-gluon plasmas. Our numerical value for the $g_{D^*D^*\rho}$ is consistent with the prediction of the effective SU(4) symmetry and vector meson dominance theory.Comment: 6 pages, 1 figure, revised versio

Analysis of the ΣQ\Sigma_Q baryons in the nuclear matter with the QCD sum rules

In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector self-energies $\Sigma_v$ and pole residues $\lambda^*_{\Sigma_Q}$ in the nuclear matter. Then we take into account the effects of the unequal pole residues from different spinor structures, and normalize the masses from the QCD sum rules in the vacuum to the experimental data, and obtain the mass-shifts $\delta M_{\Sigma_c}=-123\,\rm{MeV}$ and $\delta M_{\Sigma_b}=-375\,\rm{MeV}$ in the nuclear matter.Comment: 7 pages, 2 figures, revised versio

Mass spectrum of the scalar hidden charm and bottom tetraquark states

In this article, we study the mass spectrum of the scalar hidden charm and bottom tetraquark states with the QCD sum rules. The numerical results are compared with the corresponding ones from a relativistic quark model based on a quasipotential approach in QCD. The relevant values from the constituent diquark model based on the constituent diquark masses and the spin-spin interactions are also discussed.Comment: 19 pages, 36 figures, slight revisio

Radiative decays of the (0+,1+)(0^+,1^+) strange-bottom mesons

In this article, we assume that the $(0^+,1^+)$ strange-bottom mesons are the conventional $b\bar{s}$ mesons, and calculate the electromagnetic coupling constants $d$, $g_1$, $g_2$ and $g_3$ using the light-cone QCD sum rules. Then we study the radiative decays $B_{s0}\to B_s^* \gamma$, $B_{s1}\to B_s \gamma$, $B_{s1}\to B_s^* \gamma$ and $B_{s1}\to B_{s0} \gamma$, and observe that the widths are rather narrow. We can search for the $(0^+,1^+)$ strange-bottom mesons in the invariant $B_s \pi^0$ and $B^*_s \pi^0$ mass distributions in the strong decays or in the invariant $B_s^*\gamma$ and $B_s\gamma$ mass distributions in the radiative decays.Comment: 16 pages, 4 figures, revised versio

Electromagnetic form-factor of the π\pi meson with light-cone QCD sum rules

In this article, we calculate the electromagnetic form-factor of the $\pi$ meson with the light-cone QCD sum rules. The numerical value $F_\pi^{p}(0) =0.999\pm 0.001$ is in excellent agreement with the experimental data (extrapolated to the limit of zero momentum transfer, or the normalization condition $F_\pi(0)=1$). For large momentum transfers, the values from the two sum rules are all comparable with the experimental data and theoretical estimations.Comment: 16 pages, 3 figures, 5 versio

Analysis of mass modifications of the vector and axial-vector heavy mesons in the nuclear matter with the QCD sum rules

In this article, we calculate the mass modifications of the vector and axial-vector mesons $D^*$, $B^*$, $D_1$ and $B_1$ in the nuclear matter with the QCD sum rules, and obtain the mass-shifts $\delta M_{D^*}=-71 \rm{MeV}$, $\delta M_{B^*}=-380 \rm{MeV}$, $\delta M_{D_1}=72 \rm{MeV}$, $\delta M_{B_1}=264 \rm{MeV}$, and the scattering lengths $a_{D^*}=-1.07 \rm{fm}$, $a_{B^*}=-7.17 \rm{fm}$, $a_{D_1}=1.15 \rm{fm}$ and $a_{B_1}=5.03 \rm{fm}$ for the $D^*N$, $B^*N$, $D_1N$ and $B_1N$ interactions, respectively.Comment: 15 pages, 12 figure

Analysis of Y(4660) and related bound states with QCD sum rules

In this article, we take the vector charmonium-like state Y(4660) as a $\psi'f_0(980)$ bound state (irrespective of the hadro-charmonium and the molecular state) tentatively, study its mass using the QCD sum rules, the numerical value $M_Y=4.71\pm0.26 \rm{GeV}$ is consistent with the experimental data. Considering the SU(3) symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states $\psi'\sigma(400-1200)$, $\Upsilon'"f_0(980)$ and $\Upsilon"'\sigma(400-1200)$ with the QCD sum rules, and make reasonable predictions for their masses.Comment: 18 pages, 32 figures, revised versio

Analysis of the X(1835)X(1835) as a baryonium state with Bethe-Salpeter equation

In this article, we take the X(1835) as a pseudoscalar baryonium state, and calculate the mass spectrum of the baryon-antibaryon bound states $p\bar{p}$, $\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$, and $\Lambda\bar{\Lambda}$ in the framework of the Bethe-Salpeter equation with a phenomenological potential. The numerical results indicate the $p\bar{p}$, $\Sigma\bar{\Sigma}$ and $\Xi\bar{\Xi}$ bound states maybe exist, and the $X(1835)$ can be tentatively identified as the $p\bar{p}$ bound state.Comment: 7 pages, 1 figure, published versio

Transitions To the Long-Resident State in coupled chaotic oscillators

The behaviors of coupled chaotic oscillators before complete synchronization were investigated. We report three phenomena: (1) The emergence of long-time residence of trajectories besides one of the saddle foci; (2) The tendency that orbits of the two oscillators get close becomes faster with increasing the coupling strength; (3) The diffusion of two oscillator's phase difference is first enhanced and then suppressed. There are exact correspondences among these phenomena. The mechanism of these correspondences is explored. These phenomena uncover the route to synchronization of coupled chaotic oscillators.Comment: 3 pages, 5 figure