Scalar mesons and glueballs in D_p-D_q hard-wall models

We investigate the light scalar mesons and glueballs in the Dp-Dq hard-wall models, including D3-Dq, D4-Dq, and D6-Dq systems. It is found that only in the D4-D6 and D4-D8 hard-wall models are the predicted masses of the qˉq scalar meson f0 scalar glueball consistent with their experimental or lattice results. This indicates that D4-D6 and D4-D8 hard-wall models are the favorite candidates of the realistic holographic QCD model.     

Gluonic Origin and Glueball Nature of Pomeron

The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 （t） used commonly in diffractive processes with a coupling strength β = 6.0 GeV^-1 is initially obtained from QCD theoretically. Our study not only reproduces the Pomeron-nucleon coupling from QCD but also clearly shows the gluonlc origin and glueball nature of Pomeron, which is a longstanding puzzle. From this investigation, we claim that Pomeron can be regarded as a Reggeized tensor glueball ζ（2230） with quantum numbers of I^GJ^PC = 0＋2＋＋. Since the tensor glueball ζ（2230） lies on the Pomeron trajectory αp（t = Mζ^2） = 2, the longstanding puzzle that no physical particle lies on the Pomeron trajectory, αp（t） = 1.08 ＋ 0.20 GeV^-2 .t, seems to be solved.     

Pseudodiagonalization-based wavefunction optimization with contracted planewave basis functions

Electronic structure calculations representing the molecular orbitals (MOs) with contracted planewave basis functions (CPWBFs) have been reported recently. CPWBFs are Fourier-series representations of atom-centered basis functions. The mathematical features of CPWBFs permit the construction of matrix–vector products, FC _o , involving the application of the Fock matrix, F , to the set of occupied MOs, C _o , without the explicit evaluation of F . This approach offers a theoretical speed-up of M/n over F -based methods, where M and n are the number of basis functions and occupied MOs, respectively. The present study reports methodological advances that permit FC _o -based optimization of wavefunction formed from CPWBFs. In particular, a technique is reported for optimizing wavefunctions by combining pseudodiagonalization techniques based on an exact representation of FC _o , approximate information regarding the virtual orbital energies, and direct inversion of the iterative subspace optimization schemes to guide the wavefunction to a converged solution. This method is found to speed-up wavefunction optimizations by factors of up to ~6 − 8 over F -based optimization methods while providing identical results. Further, the computational cost of this technique is relatively insensitive to basis set size, thus providing further benefits in calculations using large CPWBF basis sets. The results of density functional theory calculations show that this method permits the use of hybrid exchange-correlation (XC) functionals with a small increase in effort over analogous calculations using generalized gradient approximation XC functionals. © 2019 Wiley Periodicals, Inc.     

Scalar glueball in a soft-wall model of AdS/QCD

The scalar glueball is investigated in a soft-wall model of AdS/QCD.Constraints of the mass of the scalar glueball are given through an analysis of a relation between the bulk mass and the anomalous dimension.The mass of the ground scalar glueball is located at 0.96_(-0.07)~(+0.04)GeVmGl.36_(-0.10)~(+0.05)GeV.In terms of a background dilaton fieldΦ(z)=cz~2,the two-point correlation function for the scalar gluon operator is obtained.The two-point correlation function at△=4 gives a different behavior compared with the one in QCD.     

胶球寻找的实验现状

阐述了有关胶球寻找的最新实验状况, 特别是集中在确认标量和张量胶球方面的现状.     

The Colle–Salvetti Wavefunction Revisited: a Comparison Between Three Approaches for Obtaining the Correlation Energy

The correlation factor of Colle and Salvetti is studied by comparing the behavior of three different correlation functionals. The normalization, sum rule, Coulomb hole, correlation energy integrand, and the Wigner exclusion hole have all been analyzed by applying the three approaches. The results indicate that the correlation factor proposed by Colle–Salvetti is a very good choice for modeling electron correlation in atoms. The flaws appearing in the development of the Colle–Salvetti equations seem mainly due to an inadequate use of the first mean value theorem of integral calculus. The Gaussian summation used for the two-body density matrix seems to be a good approximation to obtain the correlation factor equations.     

Search for JPC=even++ glueballs in radiative decay of J/Ψ

Based on the general analysis of decay width and branching ratio of two pseudo scalar meson channels, two sets of discriminants between mesons and glueballs for I=0,JPC=even++ unflavored hadrons with the mass between 1.2 and 2.9 GeV are suggested. Known I=0, JPC=2++, f2(1525) particle is discriminated as a typical meson. The way to discriminate new I=0, JPC=even++ unflavored hadrons is discussed.     

The impact of vibrational wave function on low energy electron vibrational scattering from nitrogen molecule

The vibrational wave function of the target theoretically plays an important role in the calculation of vibrational excitation cross sections. By a careful study of the differential cross sections resulting from different vibrational wave functions we find that cross sections are susceptible to vibrational wave functions. Minor changes in the vibration wave function may cause a significant change in the cross section. Even more surprising is that by selecting a few numbers of potential models(which determine the vibrational wave functions) we can often calculate the differential scattering cross section in much closer agreement with experiment in the framework of body-frame vibrational close-coupling theory, which suggest that an accurate potential energy may play a more important role in scattering than we thought before.     

On spin wavefunctions and young orthogonal matrices

Electron spin wavefunctions are expressed in the Young orthogonal representation. The normalization factor is calculated. An explicit expression for the first column elements of the Young orthogonal matrices is obtained by a comparison to the branching diagram wavefunctions. These matrix elements are used in a multideterminant representation of the total wavefunction. © 2012 Wiley Periodicals, Inc.