Sum rules in QCD for g ηΛΛ and g πΛΣ

New relations between the Borel QCD sum rules for the strong couplings of the Σ⁰ and Λ hyperons are derived. It is shown that, using the sum rules for g _MΣΣ, M = π ⁰, η, as a starting point, one can readily obtain the corresponding sum rules for the coupling constants g _ηΛΛ and g _πΛΣ ⁰. The values of these constants are calculated in a specific parameter region.     

IR-renormalon contributions to the structure functions g 3 and g 5

We calculate the leading 1/N _f perturbative contributions to the polarized nonsinglet structure functions g ₃ and g ₅ to all orders in α_s. The contributions from the first renormalon pole are determined. It is a measure for the ambiguity of the perturbative calculation and is hypothetically assumed to dominate the power corrections. The corrections Δg ₃ and Δg ₅ are given as functions of the Bjorken variable x and turn out to be negligible. The anomalous dimensions of the leading twist operators are obtained in the next-to-leading order. Received: 10 June 1998 / Revised version: 25 September 1998     

sdgIBM微观理论方案中g玻色子的引入及其性质

介绍sdgIBM微观理论方案中g玻色子的引入过程,讨论了g玻色子的集体性,g玻色子受微观参数的影响以及和sdIBM的关系.     

Constituent quarks and g 1

We review the theory and present status of the proton spin problem with emphasis on the transition between current quarks and constituent quarks in QCD. Received: 7 January 1999 / Revised version: 12 February 1999     

Thermorheological effect on magnetoconvection in weak electrically conducting fluids under 1g or μg

The thermorheological effect on magnetoconvection in fluids with weak electrical conductivity is studied numerically under lg and μg conditions. The results with a non-linear thermorheological equation considered in the problem when compared with those of the classical approach with constant viscosity delineate the fact that the latter approach results in an over-prediction of the critical eigenvalue. The results have possible astrophysical applications involving sunspots as also in space applications under /ig. Article presented at the International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore; India.     

Rotation-vibration analysis of the Coriolis-coupled ν5g, ν6g, ν8g and ν9 bands of H2CCO

Medium resolution infrared grating spectra of gaseous ketene, H₂CCO were recorded between 1000 and 400 cm^?1, both at instrument temperature (40°C) and with cooling (?40°C). Interferometric Fourier spectra were also measured at ?70°C with resolution 0.22 cm^?1 between 450 and 330 cm^?1. The K structure of the fundamentals ν₅, ν₆, ν₈, and ν₉ was assigned. These fundamentals are coupled by a-axis Coriolis interactions. These couplings were analysed on the symmetric top basis for setting up the perturbation matrix and by utilizing the K-dependent Coriolis shifts of levels. A preliminary analysis of the Coriolis intensity anomalies was also undertaken.Band center values from combination differences are $\text{ν}{}_5{}^0\text{= 587.30 (27)}$ and $\text{ν}{}_6{}^0\text{= 528.36 (39)}\text{cm}{}^{\mathrm{?1}}$. Synthetic spectra indicate the band origins of ν₈ and ν₉ to be close to 977.8 and 439.0 cm^?1, respectively. Estimates of Coriolis coupling constants obtained from synthetic spectra are $\text{ζ}{}_{58}{}^{\mathrm{a}}\text{= + 0.33 (5)}$, $\text{ζ}{}_{68}{}^{\mathrm{a}}\text{= + 0.714 (20)}$, $\text{ζ}{}_{59}{}^{\mathrm{a}}\text{= ? 0.774 (20)}$, and $\text{ζ}{}_{69}{}^{\mathrm{a}}\text{= ? 0.30 (2)}$. Approximate ratios of unperturbed vibrational transition moments obtained from spectral simulations are $\text{M}{}_8{}^0\text{:±iM}{}_5{}^0\text{:±iM}{}_6{}^0\text{:M}{}_9{}^0\text{≈ +2:?9:+10:+0.5}$.     

The decay of93g Ru,93m Ru,91g Mo,91m Mo,91g Tc and91m Tc

Decay studies on a number of short-lived odd nuclei in theN=50 region are described. The 59.6-s ⁹³Ru ground state decay was studied in detail for the first time; in these experiments the 10.8-s activity^93m Ru was discovered. The⁹¹Tc activities were also observed for the first time. The ground state and an isomeric state of this nucleus decay with nearby equal half-lives (3.14 and 3.3-min). The activities^91g Mo (16.6-min) and^95m Mo (65.1-s) have been reinvestigated. A number ofγ-rays, previously erroneously assigned to the⁹¹Mo activities, could be eliminated. A strong similarity is noted for the decay schemes of theN=49 isotones^91m Mo and^93m Ru. The energy of the 1/2^? isomeric state in⁹³Ru and theB(M4)-value of the isomeric transition fit well into the systematics of the previously knownN=49 isotones.     

Zeeman structure of the 1s5g and 1s6g configurations of helium

The splitting of levels of the 1s5g and 1s6g configurations of the helium atom in an external magnetic field (0–160 Oe) is obtained by using the fine-structure parameters calculated semiempirically. For each configuration, more than 50 crossings and three anticrossings of Zeeman sublevels are determined. The calculated splittings are compared with those obtained earlier for the 1snp and 1snd configurations of a neutral helium atom.     

Der Zerfall des Rh106g

The gamma rays associated with the decay of Rh^106g have been investigated using several sizes of Ge(Li)-counters and a Ge(Li)-NaJ(Tl)-coincidence circuit. Energies and relative gamma intensities of 107 transitions have been determined. All except 5 transitions are placed in a level scheme of Pd¹⁰⁶ having states at 0, 0⁺; 511, 8, 2⁺; 1,128.0, 2⁺; 1,133.6, 0⁺; 1,228.9, 4⁺; 1,557.6, 3⁺; 1,561.9, 2⁺; 1,706.1, 0⁺; 2,001.0, 0⁺; 2,242.4, 1, 2^±; 2,278.0, 0⁺; 2,308.6, 1, 2⁺; 2,350.8, 4⁺; 2,438.6, 1, 2⁺; 2,500.4, 0⁺; 2,525.3, 1, 2^±; 2,624.4, 0⁺; 2,706.6, 1, 2⁺; 2,741.0, 1, 2^±; 2,783.5, (2)^±; 2,821.2, 2⁺; 2,829.8, 0⁺; 2,878.3, 0⁺; 2,902.7, 2⁺; 2,917.8, 2⁺; 3,027.1, 1,2^±; 3,037.2, 1,2⁺; 3,055.2,1, 2⁺; 3,083.2, 2⁺; 3,163.4, 1,2⁺; 3,167.5, 1,2⁺; 3,221.2, 0⁺; 3,295.6, 0⁺; 3,321.3 keV, 0⁺.     

Studies of 213g, mRa and 214g, mRa by α and γ decay

The decay of ^{213, 214}Ra was studied by α-γ and γ-γ coincidence measurements. The nuclei were produced in the reactions ¹⁷⁰Er(⁴⁸Ca, xn)^218-x Ra and ¹⁷⁰Er(⁵⁰Ti, 3n)²¹⁷Th and subsequent α decay of ²¹⁷Th to ²¹³Ra. Evaporation residues recoiling out of the target were separated in-flight by the velocity filter SHIP and implanted into a position-sensitive 16-strip PIPS detector in order to study their subsequent decays. Associated γ-rays were detected by a four-fold Ge-Clover detector. In the present work we extracted new and improved data for ^{213, 214}Ra including isomeric transitions. The results are discussed and compared with previously published data.     

Decay of90m,g Rb

The decay of mass separated⁹⁰Rb has been studied usingβ,γ and conversion electron spectrometers in single and coincidence modes. The half-lives of the ground state and the isomeric level have been confirmed to be 162± 3 and 258±4 s, respectively. Theγ-rays from the decays of ground state and metastable state have been identified by measuring the decay of individual photopeaks using Ge(Li) detectors. The multipolarity of the 106.6 keV isomeric transition has been determined to beM3. Separate decay schemes of the ground and metastable states are presented. The levels of⁹⁰Sr are discussed in terms of the available experimental and theoretical information. Radioactivity.^90m,gRb [from²³⁸U(p, f)]; measuredT _1/2,E _γ,I _γ,γ—γ coin,I _ce,cc,E _β deduced logft,⁹⁰Sr levels, mass separated⁹⁰Rb.     

Experimental g factor of hydrogenlike silicon-28

Using the first principles calculations, the mixed Au _n Zn _m ⁺ (n + m ?? 6) cluster cations and their monocarbonyls Au _n Zn _m CO⁺ have been investigated at the PW91 level. For the small Au _n Zn _m ⁺ , most ground-state isomers are planar structures. A significant odd-even oscillation of the highest occupied-lowest unoccupied molecular orbital energy gaps with the number of Au atoms is observed. Upon CO adsorption, the top site and C head-on adsorptions are most favorable in energy. Moreover, the optimized geometries indicate that the CO molecule prefers binding to Au atom of the Au _n Zn _m ⁺ clusters, which can be understood by the frontier molecular orbital theory in detail. From the theoretical calculations, the CO charge population, CO binding energy (BE) and the Gibbs free-energy change ??G generally decrease with the increase of the Zn content. It is found that the BE is highly related to the electron transfer between CO and the cluster cations. Furthermore, a linear correlation between ??G and the CO BE is found. The red shift in the CO stretching frequency is sensitive to the cluster size and composition. Our calculation suggests that CO reactive collision on Au₃Zn⁺ and Au₂Zn ₂ ⁺ may lead to the dissociation of the clusters with a Zn atom loss.     

g Factors for high-spin states of238U

Calculations of the g-factor and the moment of inertia J for high-spin states of²³⁸U are performed using the model which is based on the cranking Hartree-Fock-Bogolyubov (CHFB) theory. Importance of the state-dependent pairing force on 3(ω²) is investigated.     

Nonrelativistic QED approach to the bound-electron g factor

Within a systematic approach based on nonrelativistic quantum electrodynamics, we derive the one-loop self-energy correction of order alpha(Z alpha)(4) to the bound-electron g factor. In combination with numerical data, this analytic result improves theoretical predictions for the self-energy correction for carbon and oxygen by an order of magnitude. Basing on one-loop calculations, we obtain the logarithmic two-loop contribution of order alpha(2)(Z alpha)(4)ln([(Z alpha)(-2)] and the dominant part of the corresponding constant term. The results obtained improve the accuracy of the theoretical predictions for the 1S bound-electron g factor and influence the value of the electron mass determined from g-factor measurements.     

\mathfrak{g}-Relative Star Products

We consider Kontsevich star products on the duals of Lie algebras. Such a star product is relative if, for any Lie algebra, its restriction to invariant polynomial functions is the usual pointwise product. Let be a fixed Lie algebra. We shall say that a Kontsevich star product is -relative if, on ^*, its restriction to invariant polynomial functions is the usual pointwise product. We prove that, if is a semi-simple Lie algebra, the only strict Kontsevich -relative star products are the relative (for every Lie algebras) Kontsevich star products.     

Ab Initio Investigation of the ellipsis pi(2)(g) (X(3)Sigma(-)(g), 1(1)Delta(g), 1(1)Sigma(+)(g)) Electronic States of NCN. Study of the Renner-Teller Effect in the 1(1)Delta(g) State

Large-scale CI calculations are carried out to obtain accurate potential energy surfaces for the ellipsis pi(2)(g) manifold (X(3)Sigma(-)(g), 1(1)Delta(g), 1(1)Sigma(+)(g)) of electronic states of NCN. Separation of the low-lying singlet states from the triplet ground state is computed in close agreement with the results of a recent photoelectron study by T. R. Taylor, R. T. Bise, K. R. Asmis, and D. M. Neumark [Chem. Phys. Lett. 301, 413-416 (1999)]. Vibronic coupling (Renner-Teller effect) in the 1(1)Delta(g) state is studied by means of a perturbative and a variational approach. Results of the present ab initio study confirm explicitly the rho(4) dependence postulated for the splitting of bending potential curves in Delta electronic states at small deviations from linearity. Copyright 2000 Academic Press.