204926501
Covariant tensor formalism for partial wave analyses of psi decays into gamma B anti-B
Recently BES2 collaboration observed an enhancement near the $p\bar p$ invariant mass spectrum. Using the covariant tensor formalism, here we provide theoretical formulae for the partial wave analysis (PWA) of the $\psi$ radiative decay channels $\psi \to \gamma p\bar p, \gamma\Lambda\bar \Lambda, \gamma\Sigma \bar\Sigma, \gamma\Xi\bar \Xi$ . By performing the Monte Carlo simulation, we give the angular distributions for the photon and proton in the process of $J/\psi \to \gamma p\bar p$, which may serve as a useful reference for the future PWA on these channels.
122217753
THE BOUND STATE EQUATION FOR TWO GLUONS AND ITS SOLUTION
We derive the bound state equation for two gluons in relativistic quantum field theory, i.e. the Bethe–Salpeter (BS) equation for two gluons. To solve it, we choose the kernel as the sum of a one-gluon exchange potential, a contact interaction and a linear confining potential. Under instantaneous approximation, this BS equation is solved numerically. The spectrum and the BS wave function of the glueballs are obtained in this framework. The numerical results are in agreement with that of recent lattice calculation.
16008283
A New Approach to Construct the Operator on Lattice for the Calculation of Glueball Masses
We develop a new approach to construct the operator on lattice for the calculation of glueball mass, which is based on the connection between the continuum limit of the chosen operator and the quantum number $J^{PC}$ of the state studied. The spin of the state studied is then determined uniquely and directly in numerical simulation. Furthermore, the approach can be applied to calculate the mass of glueball states (ground or excited states) with any spin $J$ including $J\geq 4$. Under the quenched approximation, we present pre-calculation results for the masses of $0^{++}$ state and $2^{++}$ state, which are $1754(85)(86)MeV$ and $2417(56)(117)MeV$, respectively.
124930294
A Rigorous Calculation for the Radiator in e~+ e~-Process
Using the precise expression of electron, positron distribution function we obtained earlier, we derive the rigorous analytical expression of radiator in e~+e~- collision process. This series expression converges rapidly to the precise result required. The comparison with existing approximate expression is also given. Our result benefits the precice calculation for the radiative corrections in e~+e~- collision processess.
15138971
The first calculation for the mass of the ground 4(++) glueball state on lattice
Under the quenched approximation, we perform a lattice calculation for the mass of the ground 4(++) glueball state in E++ channel on a D = 3+1 lattice. Our calculation shows that the mass of this state is M-G(4(++)) = 3.65(6)(18) GeV, which rules out the 4(++) or mainly 4(++) glueball state interpretation for xi(2230).
126028323
THE PRODUCTION PROCESS OF △ (1236) BY HIGH ENERGY NEUTRINOS, ACCORDING TO THE STRATON MODEL
116901981
Further evidence for the Sigma* resonance with J**P = 1/2- around 1380-MeV
The unquenched quark models predict the new particle $\Sigma^*$ with spin parity $J^P=1/2^-$ and its mass is around the well established $\Sigma^*(1385)$ with $J^P=3/2^+$. Here by using the effective Lagrangian approach we study \kp\ reaction at the range of $\Lambda^{*}(1520)$ peak, comparing the resulting total cross section, and $\pi^+\pi^-$, $\Lambda\pi^+$, $\Lambda\pi^-$ invariant squared mass distributions for various incident $K^-$ momenta, as well as the production angular distribution of the $\Lambda$ with the data from the Lawrence Berkeley Laboratory 25-inch hydrogen bubble chamber, we find that, apart from the existing resonance $\Sigma^{*}(1385)$ with $J^P=3/2^+$, there is a strong evidence for the existence of the new resonance $\Sigma^{*}$ with $J^P=1/2^-$ around 1380 MeV. Higher statistic data on relevant reactions are needed to clarify the situation.
120073554
Emergence of gap from holographic fermions on charged Lifshitz background
A bstractWe report a dynamical formation of a gap from holographic fermions with dipole coupling on charged Lifshitz background. For a large enough dipole coupling, a gap opens as that found in RN-AdS background. By studying the density of states A(ω), one shows that the onset of the gap is near p ≃ 4.8 for the case of q = 2 and mζ = 0 and the width of the gap becomes larger as the strength of the interaction keeps increasing. Similar with that found in RN-AdS black hole, there are also a transfer of spectral weight over all energy scales by tuning the dipole coupling. Finally, a brief discussion on the effect of the dynamical exponent z is also presented.
106116857
Study of K- p ---> Lambda pi+ pi-, Lambda pi0 and gamma N ---> K+ Sigma*
117757882
A new regularization of loop integral, no divergence, no hierarchy problem
We find a new regularization scheme which is motivated by the Bose-Einstein condensation. The energy of the virtual particle is considered as discrete. Summing them and regulating the summation by the Riemann $\zeta$ function can give the result of loop integral. All the divergences vanish, we can get almost the same results as Dimensional Regularization. The prediction beyond Dimensional Regularization is also shown in the QED. The hierarchy problem of the radiative correction of scalar mass completely vanish.
16931057
A Statistical Analysis of Point-like Sources in the Chandra Galactic Center Survey ∗
The Chandra Galactic Center Survey detected similar to 800 X-ray point-like sources in the 2 degrees x 0.8 degrees sky region around the Galactic Center. We study the spatial and luminosity distributions of these sources according to their spectral properties. Fourteen bright sources detected are used to fit jointly an absorbed power-law model, from which the power-law photon index is determined to be similar to 2.5. Assuming that all other sources have the same power-law form, the relation between hardness ratio and HI column density N-H is used to estimate the NH values for all sources. Monte Carlo simulations show that these sources are more likely concentrated in the Galactic center region, rather than distributed throughout the Galactic disk. We also find that the luminosities of the sources are positively correlated with their HI column densities, i.e., a more luminous source has a higher HI column density. From this relation, we suggest that the X-ray luminosity comes from the interaction between an isolated old neutron star and interstellar medium (mainly dense molecular clouds). Using the standard Bondi accretion theory and the statistical information of molecular clouds in the Galactic center, we confirm this positive correlation and calculate the luminosity range in this scenario, which is consistent with the observation (10(32)-10(35) erg s(-1)).