A semi-empirical correlation energy for nuclei

A semi-empirical interaction is used to calculate higher order corrections to the binding energies of even—even nuclei close to the line of stability. These corrections are taken to come from two phonon configurations and are treated as a perturbation with respect to the BCS nuclear ground state which is obtained from applying the energy density method to finite nuclei. The overall correspondence between theory and experiment for the 60 nuclei calculated between A =52 and A =234 is good, with excellent agreement for the non-deformed nuclei situated within the regions A = 72 to 144 and A = 200 to 212. The large correction enegies (several MeV per nucleus on the average) indicate that these correlations are of importance for explaining nuclear binding energies and that it is necessary to include them within energy functional itself. The fact that these correlations come almost exclusively from nucleons close to the fermi surface is also discussed.     

The correlation energy of anisotropic metals

The effect of a spatially periodic field on the correlation energy of metallic electrons is studied. The crystal potential is taken to vary in one dimension only. It may be arbitrarily strong, but an implicit form is chosen so as to generate specially simple Bloch states (the ‘sinusoidal electron model’). Electronic motion in the plane normal to the crystal field is assumed free. The constantenergy surfaces are taken to be ellipsoids of revolution. An explicit representation of the crystal field is not required. It is found that specifically crystalline effect—such as Umklapp scattering—do not play an important role, and that the main effect of interband scattering is merely a shift in the constant term in the correlation energy. On the other hand the ellipticity of the energy surfaces does lead to significant modifications to the free-electron expression.     

Effect of correlation on energy of solids

In the present paper we make an attempt to model the lattice energy with the lattice constants through the first-principles calculations. This formalism is designed particularly for application with the self-consistent pseudopotential (PP) method within the density functional (DF) framework and includes exchange and correlation effects. Applying the above formalism we have calculated the lattice energy and correlation energy for a number of solids belonging to groups I–VII and II–VI of the periodic table. The convergence of our results is in the favour of used PP. These results will be helpful in determining various structural and elastic properties of these solids and in the generation of equation of state.     

Electron correlation energy in confined two-electron systems

Radial, angular and total correlation energies are calculated for four two-electron systems with atomic numbers Z=0-3 confined within an impenetrable sphere of radius R. We report accurate results for the non-relativistic, restricted Hartree-Fock and radial limit energies over a range of confinement radii from 0.05-10a₀. At small R, the correlation energies approach limiting values that are independent of Z while at intermediate R, systems with Z?1 exhibit a characteristic maximum in the correlation energy resulting from an increase in the angular correlation energy which is offset by a decrease in the radial correlation energy.     

Left-right asymmetry for meson production in SIDIS proces

We analyze the left-right asymmetry in the semi-inclusive deep inelastic scattering （SIDIS） process using a method where no weighting function are used. Considering all flavor of quarks, we reanalyze the π±production and extend our calculation on the K± production. The predictions on HERMES, COMPASS and JLab kinematics with transversely polarized nucleon target are shown in this paper.     

Left-right symmetry and finite one-loop Dirac neutrino mass

We present a modified version of the left-right symmetric model that includes a charged singlet scalar boson where the neutrino is massless at the tree level and acquires a smal and finite Dirac mass at the one-loop level. In the case if three families of fermions, it predicts m_ve=0 and the other two neutrinos are massive with v_τ lighter than v_v. The model also predicts large magnetic moments and v_μ→v_e+ψ decay rates. The new feature of the model is the inclusion of singlet charged heavy fermions which mix with the light quarks and leptons, leading to the existence of tree-level flavor-changing neutral currents, which can provide tests of the model.     

Left-right asymmetry for meson production in SIDIS process

We analyze the left-right asymmetry in the semi-inclusive deep inelastic scattering (SIDIS) process using a method where no weighting function are used. Considering all flavor of quarks, we reanalyze the π~± production and extend our calculation on the K~± production. The predictions on HERMES, COMPASS and JLab kinematics with transversely polarized nucleon target are shown in this paper.     

Left-right asymmetry in Compton scattering on polarized electrons

In Compton scattering on polarized electrons a left-right asymmetry of the order 10⁻³ has been observed which must be attributed to higher-order corrections of the scattering amplitude. This effect might provide a test of quantum electrodynamics.     

Forward-backward multiplicity correlation in high energy hadron-hadron collisions

The forward-backward multiplicity correlation over the full pseudorapidity range forpp andp \(\bar p\) collisions at ISR and Collider energies have been analysed in terms of a Chou-Yang Type multiplicity distribution which consists of a stochastic (binomial) component forz=n _F ?n _B and a nonstochastic (negative binomial) component forn=n _F +n _B . Reasonable agreement with experimental data is obtained if the final-state particles are assumed, in a cluster model, to be created by the decay of clusters with a mean cluster size (charged particles per cluster) which is energy-dependent.     

聚合物中长程关联能的动力学研究

本文计算采用扩展的SSH哈密顿模型,加上长程关联哈密顿量,在自然边界条件下,用绝热动力学方法研究了有限长反式聚乙炔链中平均关联能随时间的演化,计算了长程电子关联对极化子动力学的影响并计算了极化子状态下的长程关联能.结果发现,加入一个电子或空穴,平均关联能的大小随着时间呈非周期性阻尼振荡,经过一定时间后,平均关联能趋近一个恒定值,此时得到比较稳定的极化子位形.当格点增加时,长程关联能趋于恒定的时间逐渐缩短.     

Gamma-ray angular correlation in intermediate energy proton-nucleus scattering

The role of γ-ray angular correlation in intermediate energy proton scattering is examined. By using polarized incident proton, detecting the polarization of the scattered particle, and/or the polarization of the emitted γ-ray, information unavailable otherwise can be obtained including a determination of the (8J_f + 3) pieces of independent parameters in the scattering amplitude from a 0⁺ target.     

Non-local exchange correlation energy in quasi-two-dimensional electron layers

We introduce a simple, non-local approximation for the exchange-correlation energy of an inhomogeneous electron gas. This approximation is shown to be quantitatively accurate in several important limiting cases. The method is used to calculate the non-local exchange-correlation energy for density distributions representing quasi-two-dimensional electron layers. These energies are compared to the widely used three-dimensional local-density approximation and suggest that the latter approximation may contain errors on the order of 10–30% for layer profiles typical of real systems.     

Left-right symmetry breaking scale and supersymmetry in unified theories

We propose a class of supersymmetric grand unified models where parity and SU(2)_R breaking scales are widely separated and compatible with a low-lying mass for the right-handed gauge boson W_R. The intermediate symmetry SU(4)_c×SU(2)_L×SU(2)_R and Higgs content are uniquely fixed if m_WR < 10⁹ GeV. The unification scale lies within an order of magnitude below the Planck mass.