119402221
Ground state mass spectrum for scalar diquarks with Bethe-Salpeter equation
In this article, we study the structures of the pseudoscalar mesons $\pi$, $K$ and the scalar diquarks $U^a$, $D^a$, $S^a$ in the framework of the coupled rainbow Schwinger-Dyson equation and ladder Bethe-Salpeter equation with the confining effective potential. The $u$, $d$, $s$ quarks have small current masses, and the renormalization is very large, the mass poles in the timelike region are absent which implements confinement naturally. The Bethe-Salpeter wavefunctions of the pseudoscalar mesons $\pi$, $K$ and the scalar diquarks $U^a$, $D^a$, $S^a$ have the same type (Gaussian type) momentum dependence, center around zero momentum and extend to the energy scale about $q^2=1GeV^2$ which happen to be the energy scale for the chiral symmetry breaking, the strong interactions in the infrared region result in bound (or quasi-bound) states. The numerical results for the masses and decay constants of the $\pi$, $K$ mesons can reproduce the experimental values, the ground state masses of the scalar diquarks $U^a$, $D^a$, $S^a$ are consistent with the existing theoretical calculations. We suggest a new Lagrangian which may explain the uncertainty of the masses of the scalar diquarks .
16260034
Axial form-factor and induced pseudoscalar form-factor of the nucleons
We calculate the axial and the induced pseudoscalar form-factors GA(t=-Q2) and GP(t=-Q2) of the nucleons in the framework of the light-cone QCD sum-rules approach up to twist-6 three valence quark light-cone distribution amplitudes, and observe that the form-factors GA(t=-Q2) and GP(t=-Q2) at intermediate and large momentum transfers with Q2>2 GeV2 have significant contributions from the end-point (soft) terms. The numerical values for the axial form-factor GA(t=-Q2) are compatible with the experimental data and theoretical calculations; for example, the chiral quark models and lattice QCD. The numerical values for the induced pseudoscalar form-factor GP(t=-Q2) are compatible with the calculation from the Bethe–Salpeter equation.
14097903
Magnetic moment of the pentaquark Θ+(1540) as diquark-diquark-antiquark state with QCD sum rules
Abstract.In this article, we study the magnetic moment of the pentaquark state Θ+(1540) as a diquark-diquark-antiquark ($[ud][ud]\bar{s}$) state with the QCD sum rules in an external weak electromagnetic field (EFSR) and the light-cone QCD sum rules (LCSR) respectively. The numerical results indicate that the magnetic moment is about $\mu_{\Theta^ + } = -(0.11\pm 0.02)\mu_N$ for the EFSR and $\mu_{\Theta^ + }\approx-(0.1$-$0.5)\mu_N$ for the LCSR. As the values obtained from the EFSR are more stable than the corresponding ones from the LCSR, $\mu_{\Theta^ + } = -(0.11\pm 0.02)\mu_N$ is more reliable.
260040
CP violation in chargino decays in the MSSM
In the minimal supersymmetric standard model (MSSM) with complex parameters, supersymmetric loop effects can lead to $\mathrm{CP}$ violation. We calculate the rate asymmetries of decays of charginos into the lightest neutralino and a W boson on the basis of the most important loop contributions in the third generation squark sector. It turns out that the $\mathrm{CP}$ violating asymmetries can be a few percent in typical regions of the parameter space of the MSSM. These processes would provide very promising channels for probing $\mathrm{CP}$ violation in the MSSM at future high-energy colliders.
255344
Scalar form-factor of the proton with light-cone QCD sum rules
We calculate the scalar form factor of the proton in the framework of the light-cone QCD sum rules approach with the three valence quark light-cone distribution amplitudes up to twist-6 and observe the scalar form factor {sigma}(t=-Q{sup 2}) at intermediate and large momentum transfers Q{sup 2}>2 GeV{sup 2} has significant contributions from the end point (or soft) terms. The numerical values for the {sigma}(t=-Q{sup 2}) are compatible with the calculations from the chiral quark model and lattice QCD at the region Q{sup 2}>2 GeV{sup 2}.
119409718
Decay constants of the pseudoscalar mesons in the framework of the coupled Schwinger–Dyson equation and Bethe–Salpeter equation
Abstract In this article, we investigate the structures of the pseudoscalar mesons ( π , K , D , D s , B and B s ) in the framework of the coupled rainbow Schwinger–Dyson equation and ladder Bethe–Salpeter equation with the confining effective potential (infrared modified flat bottom potential). The Schwinger–Dyson functions for the u , d and s quarks are greatly renormalized at small momentum region and the curves are steep at about q 2 = 1 GeV 2 which indicates an explicitly dynamical symmetry breaking. The Euclidean time Fourier transformed quark propagators have no mass poles in the time-like region which naturally implements confinement. As for the c and b quarks, the current masses are very large, the renormalization are more tender, however, mass poles in the time-like region are also absent. The Bethe–Salpeter wavefunctions for those mesons have the same type (Gaussian type) momentum dependence and center around small momentum which indicate that the bound states exist in the infrared region. The decay constants for those pseudoscalar mesons are compatible with the values of experimental extractions and theoretical calculations, such as lattice simulations and QCD sum rules.
119131972
Determinant representations of scalar products for the open XXZ chain with non-diagonal boundary terms
The determinant representation of the scalar products of the Bethe states of the open XXZ spin chain with non-diagonal boundary terms is studied. Using the vertex-face correspondence, we transfer the problem into the corresponding trigonometric solid-on-solid (SOS) model with diagonal boundary terms. With the help of the Drinfeld twist or factorizing F-matrix, we obtain the determinant representation of the scalar products of the Bethe states of the associated SOS model. By taking the on shell limit, we obtain the determinant representations (or Gaudin formula) of the norms of the Bethe states.
17301039
The Color Excesses of Type Ia Supernovae from Single-Degenerate Channel Model
Single Degenerate model is the most widely accepted progenitor model of type Ia supernovae (SNe Ia), in which a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from a main sequence or a slightly evolved star (WD +MS) to increase its mass, and explodes when its mass approaches the Chandrasekhar mass limit. During the mass transfer phase between the two components, an optically thick wind may occur and the material lost as the wind may exist as circumstellar material (CSM). Searching the CSM around progenitor star is helpful to discriminate different progenitor models of SNe Ia. Meanwhile, the CSM is a source of color excess.The purpose of this paper is to study the color excess produced from the single-degenerate progenitor model with optically thick wind, and reproduce the distribution o f color excesses of SNe Ia. Meng et al. (2009) systemically carried out binary evolution calculation of the WD +MS systems for various metallicities and showed the parameters of the systems before Roche lobe overflow and at the moment of supernova explosion in Meng & Yang (2009). With the results of Meng et al. (2009), we calculate the color excesses of SNe Ia at maximum light via a simple analytic method.We reproduces the distribution of color excesses of SNe Ia by our binary population synthesis approach if the velocity of the optically thick wind is taken to be of order of magnitude of 10 km s −1 . However, if the wind velocity is larger than 100 km s −1 , the reproduction is bad.
119330352
Determinant formula for the partition function of the six-vertex model with a non-diagonal reflecting end
With the help of the F-basis provided by the Drinfeld twist or factorizing F-matrix for the open XXZ spin chain with non-diagonal boundary terms, we obtain the determinant representation of the partition function of the six-vertex model with a non-diagonal reflecting end under domain wall boundary condition. © 2010 Elsevier B.V.
124766319
COMPUTATION OF DIMENSIONS FOR STRANGE ATTRACTORS BY THE BOX COUNTING RENORMALIZATION METHOD
The scaling ansats for box counting functions is verified numerically for the reverse doubling sequence of the logistic map. A box counting renormalisation method is developed to calculate dimensions for strange attractors.
16315336
Eigenvalues of Ruijsenaars–Schneider models associated with An−1 root system in Bethe ansatz formalism
Ruijsenaars–Schneider models associated with An−1 root system with a discrete coupling constant are studied. The eigenvalues of the Hamiltonian are given in terms of the Bethe ansatz formulas. Taking the “nonrelativistic” limit, we obtain the spectrum of the corresponding Calogero–Moser systems in the third formulas of Felder et al.