B_u→ψM decays and S-D wave mixing effects

The B_u →ψM decays are studied with the perturbative QCD approach, where the psion ψ = ψ(2S),ψ(3770), ψ(4040) and ψ(4160), and the light meson M = π, K, ρ and K*. The factorizable and non-factorizable contributions, and the S-D wave mixing effects on the psions, are considered in the calculation. With appropriate inputs, the branching ratios for the B_u →ψK decays are generally coincident with the experimental data within errors. However, due to the large theoretical and experimental errors, it is impossible for the moment to give a severe constraint on the S-D wave mixing angles.     

3 S 1−3 D 1 mixing and E1 radiative transitions in charmonium

The radiative transitions ψ′→γ+χ _J and χ _J →γ+ψ are studied in the quark model with the ψ and ψ′ interpreted conventionally as³ S ₁ \(c\bar c\) states and the χ _J as³ P _J \(c\bar c\) states. In particular, the effect of³ S ₁?³ D ₁ mixing on the decay widths is calculated. The photon angular distributions in these decays are also studied and are found to be a more sensitive test of³ D ₁ admixtures in the Ψ states. The³ D ₁ content of the Ψ is found to be large but the estimate is very sensitive to the photon angular distributions. More precise measurements could help to explain the large ψ″ leptonic width.     

Production of charmonium（like）states in e^＋e^- interactions

We present a search for new charmonium like states in e~ e~- annihilation using the initial-state radiation and the process e~ e~-→J/ψD~(*)~(*).The analyses are based on a huge data sample recorded near theγ(4S)resonance with the Belle detector at the KEKB e~ e~- asymmetric-energy collider.     

The theoretical character of the X^1∑^＋ and A^1∑^＋ states of ScN

This paper calculates the potential energy curves (PECs) of the ground state (X 1 Σ + ) and excited state (A 1 Σ + ) of ScN molecule by multireference configuration interaction method. The correct character of the PECs has been gripped while they had been improperly reported in the literature. Based on the PECs, the spectroscopic parameters and vibrational energy levels are determined, and compared with experimental data and other theoretical works available at the present.     

n - \bar n transitions in nuclei and mixing of nuclear states with A and A−22

A new lower limit on the period of oscillations, sec, which follows from the stability of Fe, is found. This limit is almost 10 times larger than previous estimations. Pis’ma Zh. éksp. Teor. Fiz. 64, No. 7, 456–461 (10 October 1996) This paper is an extended version of the talk presented at the Workshop on Baryon Instability Searches, Oak Ridge, March 1996. Published in English in the original Russian journal. Edited by Steve Torstveit.     

The production of narrow Σ-hypernuclear states

It has been suggested that some of the observed narrow Σ hypernuclear states may be “bound states in the continuum” of the Σ interacting with the host nucleus formed when that interaction is strongly absorptive. It is shown that the S matrix for such a process vanishes at the complex energy of such a bound state. Some general properties of the S matrix in the presence of absorption are derived.     

Effective λN-interaction and spectroscopy of low-lying states of 1p-shell hyernuclei

A new set of the shell-model two-particle potential parameters,S ,S _N andT forp-shell hypernuclei is proposed. The set is consistent with the available data on the excited levels of ⁷ Li, ⁹ Be, ¹⁰ B, ¹² B and ^p O. The classification of low lying states and-transitions in the 1p-shell hypernuclei is discussed in terms of the {s ⁴ p ⁿ*s :JT} configurations. The feasibility for the excited bound states and for the-transitions to be observed in the spin-flip and non spin-flip single-nucleon reactions is examined in detail.The authors are indebted to R.E. Chrien for information on the experimental results [21] before publication.     

The first and second Painlevé equations of higher order and some relations between them

The first and second Painlevé equations of higher order are introduced. The relations between the Korteweg-de Vries hierarchies and their singular manifold equations are presented. These identities are used to search for the relations between the first and the second Painlevé equations of higher order.     

The fractal measurement of experimental images of supersonic turbulent mixing layer

Flow visualization of supersonic mixing layer has been studied based on the high spatiotemporal resolution Nano-based Planar Laser Scattering(NPLS) method in SML-1 wind tunnel. The corresponding images distinctly reproduced the flow structure of laminar,transitional and turbulent region,with which the fractal measurement can be implemented. Two methods of measuring fractal dimension were introduced and compared. The fractal dimension of the transitional region and the fully developing turbulence region of supersonic mixing layer were measured based on the box-counting method. In the transitional region,the fractal dimension will increase with turbulent intensity. In the fully developing turbulent region,the fractal dimension will not vary apparently for different flow structures,which em-bodies the self-similarity of supersonic turbulence.     

Exploring ground states and excited states of spin-1 Bose–Einstein condensates by continuation methods

A pseudo-arclength continuation method (PACM) is employed to compute the ground state and excited state solutions of spin-1 Bose–Einstein condensates (BEC). The BEC is governed by the time-independent coupled Gross–Pitaevskii equations (GPE) under the conservations of the mass and magnetization. The coupling constants that characterize the spin-independent and spin-exchange interactions are chosen as the continuation parameters. The continuation curve starts from a ground state or an excited state with very small coupling parameters. The proposed numerical schemes allow us to investigate the effect of the coupling constants and study the bifurcation diagrams of the time-independent coupled GPE. Numerical results on the wave functions and their corresponding energies of spin-1 BEC with repulsive/attractive and ferromagnetic/antiferromagnetic interactions are presented. Furthermore, we reveal that the component separation and population transfer between the different hyperfine states can only occur in excited states due to the spin-exchange interactions.     

The theoretical and experimental investigations of Stark structure in sodium Rydberg states atoms

The experimental results of the Stark structure of Na in the vicinity of n~*=21-23 with the external electric field from 0 to 380V/cm are reported. The theoretical calculation of the stark levels of Na based on the atomic potential model are in good agreement with experiment. The limiting error between the theory and experiment turns out to be due to experimental uncertainty.     

The logarithm of the derivative operator and higher spin algebras ofW ∞ type

We use the notion of the logarithm of the derivative operator to describeW type algebras as central extensions of the algebra of differential operators. We also provide closed formulae for the truncations ofW ₁₊ to higher spin algebras withsM, for allM2. The results are extended to matrix valued differential operators, introducing a logarithmic generalization of the Maurer-Cartan cocycle.This work was supported in part by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under Contract DE-AC03-76Sf00098 and in part by the National Science Foundation under grants PHY-85-15857 and PHY-87-17155Address after July 1, 1992: Dept. of Mathematics, Yale University, New Haven, CTO6520, USA     

The entropic squeezing of superposition of two arbitrary coherent states

In this paper the superpositions of two arbitrary coherent states ｜ψ〉 = α ｜β｜ ＋ be^iψ ｜mβe^iδ〉 are constructed by using the superposition principle of quantum mechanics. The entropic squeezing effects of the quantum states are studied. The numerical results indicate that the amplitudes, the ratio between the amplitudes of two coherent states, the phase difference between the two components and the relative phase of the two coefficients play important roles in the squeezing effects of the position entropy and momentum entropy.     

The interplay of single-particle and collective motions in the low-lying states of ■ with quadrupole-octupole correlations

The beyond mean-field approach for low-lying hypernuclear states is extended by mixing the confgurations associated with both single-particle and quadrupole-octupole collective excitations within the generator coordinate method based on a covariant density functional theory. The method is demonstrated in the application to the low-lying states of ²¹_ΛNe, where the confgurations with the Λ hyperon occupying the frst(Λ_s) and second(Λ_p) lowest-energy state...     

The effects of doubly excited states on ionization balance

The effects of highly doubly excited states on ionization balance are investigated. In the calculation, A Collisional-Radiative model in Detailed-Conflguration-Accounting （DCA） is applied to population calculations for NLTE pl＆smas. Configuration-averaged rate coefficients that needed in the rate equations are obtained based onthe first order perturbation theory. The Hatree-Fock-Slater self-consistent-field method is used to calculate theelectron wave functions. The mean ionization stage of high-Z plasma Lu is presented. The comparison shows thatthe mean ionization stage increases more than 3 stages when doubly excited states 5l6l＇ and 5l5l＇ are not included in the population calculations.     

The effects of doubly excited states on ionization balance

The effects of highly doubly excited states on ionization balance are investigated. In the calculation, A Collisional-Radiative model in Detailed-Configuration-Accounting (DCA) is applied to population calculations for NLTE plasmas. Configuration-averaged rate coefficients that needed in the rate equations are obtained based on the first order perturbation theory. The Hatree-Fock-Slater self-consistent-field method is used to calculate the electron wave functions. The mean ionization stage of high-Z plasma Lu is presented. The comparison shows that the mean ionization stage increases more than 3 stages when doubly excited states 5l6l' and 5l5l' are not included in the population calculations.     

Bound states and resonance states of the plasma-embedded tdμ and ddμ molecular ions

We have investigated the bound states and resonance states of plasma-embedded tdμ and ddμ molecular ions using accurate correlated basis functions. The plasma effect has been taken care of by considering the Debye shielding approach of plasma modeling which admits a variety of plasma conditions. The density of resonance states are calculated using the stabilization method. The ground and excited states energies, and the S-wave resonance energies of tdμ and ddμ molecular ions immersed in plasmas are reported for various shielding parameters, along with the 1S and 2S threshold energies of the tμ and dμ atoms.     

Rovibrational states of H+ 3. Part 1: The energy region below 9000 cm−1 and modelling of the non-adiabatic effects

This group's variational method for computing rovibrational energies using hyperspherical coordinates and harmonics has been applied to all H⁺ ₃ states below 13000 cm^?1 (J ≤ 10) for which accurate energies based on a submicrohartre accuracy potential energy surface have been obtained. A comparison with a recent comprehensive compilation of experimental data below 9000 cm^?1 shows deviations of up to 1.2 cm^?1. First it is shown that these deviations exert a systematic influence on the vibrational band but depend to a much lesser extent on rotational excitation. Then the remaining discrepancies can be attributed to the neglect of non-adiabatic effects, for which a useful correction formula based on ab initio results is obtained. The scatter in individual bands can thus be reduced to ~0.1 cm^?1 such that these corrected results are consistent with the accuracy of the potential energy surface itself.     

Production of charmonium(like) states in e+e－ interactions

We present a search for new charmonium like states in e⁺e^－ annihilation using the initial-state radiation and the process e⁺e^－J/ψD^(*)D^(*). The analyses are based on a huge data sample recorded near the Υ(4s) resonance with the Belle detector at the KEKB e⁺e^－ asymmetric-energy collider.