On the mass of the ss^- member of the 1^3D1 meson nonet

In the framework of Regge phenomenology and meson meson mixing, this paper estimates the mass of isoscalar state （ss^-） of the 1^3D1 meson nonet, and the results given by two different approaches are 1735.51 ± 59MeV and 1730.29 ±46.SMeV.     

Dynamical Algebras in the 1+1 Dirac Oscillator and the Jaynes–Cummings Model

We study the algebraic structure of the one-dimensional Dirac oscillator by extending the concept of spin symmetry to a noncommutative case.An SO(4) algebra is found connecting the eigenstates of the Dirac oscillator,in which the two elements of Cartan subalgebra are conserved quantities.Similar results are obtained in the Jaynes-Cummings model.     

Intensity distribution in the bands of the D1 → X1∑+ system of PbO

Relative integrated intensities of the D1 → X¹∑⁺ system of PbO have been measured by heterochromatic photography photometry. The Morse potential has been employed to compute the Franck-Condon factors and r-centroids. The variation of electronic transition moment R_e with internuclear separation r is found to be R_e(r) = const × (0.54 r − 1) in the range 1.957 ⩽ r, Å ⩽ 2.051. Relative band strengths are derived. The effective vibrational temperature of the source was 6199 K.     

Numerical Determination of the Critical Value for the （1＋1）-Dimensional Sine-Gordon Model

A new procedure of potential importance sampling method is applied to investigate the phase transition of the （1＋1）-dimensional sine-Gordon model. With this method, we obtain the Kosterlitz-Thouless-type phase transition critical value of β^2 ≌ 8π with a relative error as small as 0.4%.     

Investigation of the character of the exchange interaction in the system Hg1−xMnxSe

A new method is proposed for determining the magnetic characteristics (magnitude and sign of the exchange interaction energy and the average size of clusters of magnetic ions) of dilute solid solutions of semimagnetic semiconductors at low temperatures based on oscillation measurements. The method makes it possible to find the magnetic characteristics of the indicated systems at temperatures between the point of the transition into the spin glass state and the temperature corresponding to the characteristic binding energy of magnetic atoms in clusters, for which standard methods based on the measurement of the magnetic susceptibility are not effective. The method is used to study the character of the exchange interaction in the system of solid solutions Hg_1–xMn_xSe as a function of their composition as well as under conditions of hydrostatic compression. To this end the oscillations of the magnetoresistance (Shubnikov-de Haas (SH) effect) in single-crystalline samples of Hg_1–xMn_xSe in the region of compositions 0.001 x 0.23 in magnetic fields H up to 65 kOe at temperatures T = (0.4–20) K and pressures up to 16 kbar were studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 29–39, November, 1989.     

Field inversion of the sign of the hall coefficient in Hg1−xMnxTe1−ySey

In the temperature range T=77–300 K and H1–18 kOe, the dependence of the Hall coefficient (R_H) of crystals of Hg_1–xMn_xTe_1–ySe_y (0H=f(H), as well as the inversion of the sign of R_H as H increases for Hg_1–xMn_xTe_1–ySe_y (x0.1 and y=0.05) are explained by the presence in the samples of three types of charge carriers: holes, and heavy and light electrons.Chernovitskii University. Translated from Izvestiya Vysshykh Uchebnykh Zavedenii, Fizika, No. 4, pp. 11–14, April, 1994.     

Bounds for the limiting variance of the “heavy particle” inR 1

We consider a one-dimensional system consisting of a tagged particle of massM surrounded by a gas of unit-mass hard-point particles in thermal equilibrium. Denoting byQ _t the displacement of the tagged particle, we give lower and upper bounds — independent ofM — for. It results from the proof that the correct nontrivial norming ofQ _t — if any — is .Work supported by the Central Research Found of the Hungarian Academy of Sciences (Grant No. 476/82)     

The magnetic circular dichroism spectrum of the 1 B 2u ←1 A 1g transition of benzene in the vapour phase

The magnetic circular dichroism (MCD) spectrum of the ¹ B _2u ←¹ A _1g transition of benzene has been measured in the vapour phase. Many of the bands due to transitions between single vibronic levels display A terms. It has been shown that the angular momentum arises by vibronic mixing both of the ¹ E _1u state with the ¹ B _1u state and of the ¹ E _2g states with the ¹ A _1g ground state by e _2g vibrations. The magnitudes and signs of the experimental and calculated ratios, A/D, for the A ₀ ⁰ vibronic origin are in excellent agreement. Two strong MCD progressions of opposite sign with B-term dispersion have been observed in regions of low absorption. These are identified with vibronic origins due to the v ₈ and v ₉ e _2g modes. By contrast the MCD spectrum of hexadeuterobenzene vapour has a much lower magneto-rotational strength and displays none of the striking features of the benzene MCD spectrum.     

A scanning tunneling microscopy investigation of the 1 × 2 ⇌ 1 × 1 structural transformation of the pt(110) surface

Lifting of the reconstruction of the clean Pt(110) surface under the influence of adsorbed CO proceeds at 300 K through homogeneous nucleation of small holes (with about 10 × 10 Ų size). At 350 K more correlated displacements of [110] strings take place, a characteristic shared with the reverse process, namely the restoration of the 1× 2 phase after desorption.     

Analysis of the High-Resolution Infrared Spectrum of the PHD2 Molecule: ν1 and 2ν1 Bands

The results of investigation into the infrared spectra of the PHD₂ molecule including the ₁ fundamental band centered at 2324.005 cm^–1 (with a resolution of 4.2·10^–3 cm^–1) and the first 2₁ valence overtone centered at 4563.634 cm^–1 (with a resolution of 8.8·10^–3 cm^–1) are given in the present paper. Based on an analysis of the results obtained, 1340 and 1020 lines are referred to the ₁ and 2₁ bands, respectively. This data are used to calculate 316 and 248 vibrational-rotational energies of the (100000) and (200000) excited vibrational states, respectively. Since both bands can be considered as isolated, we take advantage of the Watson Hamiltonian (the reduction A in the I ^r representation) to describe their rotational structure. The calculated spectroscopic parameters of the examined states of the PHD₂ molecule correlate well with each other and with the corresponding parameters of the ground vibrational state.     

On the Lieb-Thirring constantsL γ,1 for γ≧1/2

LetE _i(H) denote the negative eigenvalues of the one-dimensional Schrödinger operatorHu??u″?Vu,V≧0, onL ₂(∝). We prove the inequality (1) $$\mathop \sum \limits_i |E_i (H)|^{ \gamma } \leqq L_{\gamma ,1} \mathop \smallint \limits_\mathbb{R} V^{\gamma + 1/2} (x)dx,$$ for the “limit” case γ=1/2. This will imply improved estimates for the best constantsL _γ,1 in (1) as 1/2<γ<3/2.     

Transition probabilities of the X1Σ+, A1Π, B1Δ, C1Σ+, and D1Π states of the AlO+ cation

ABSTRACT

This study computes the potential energy curves of the X¹Σ⁺, A¹Π, B¹Δ, C¹Σ⁺, and D¹Π states of AlO⁺ cation and the transition dipole moments between them. The orders of the rotationless radiative lifetimes are 10–100?μs for the A¹Π state, 1–1000?ms for the B¹Δ state, 10?ns for the first well and 100?ns for the second well of the C¹Σ⁺ state, and 1?μs for the D¹Π state. Emissions of the B¹Δ–A¹Π and D¹Π–C¹Σ⁺ systems are so weak that they are hardly measured via spectroscopy, the emissions of the C¹Σ⁺–X¹Σ⁺, C¹Σ⁺–A¹Π, and D¹Π–X¹Σ⁺ systems are so strong that they can be detected readily, and emissions of the A¹Π–X¹Σ⁺ and D¹Π–A¹Π systems can be observed through spectroscopy only by a significant effort. There is a strong great similarity between spontaneous emissions of the A¹Π–X¹Σ⁺ system of the AlO⁺ cation and the A²Π–X²Σ⁺ system of the AlO radical. The emissions of the A²Π–X²Σ⁺ system of the AlO radical have been measured in outer space Therefore, it is highly possible that the emissions of the A¹Π–X¹Σ⁺ system of the AlO⁺ cation can be detected in the astrophysical media.     

On the magnetic susceptibility of Pd1−x Ag x in the range 0.5≦x≦1

The weak variation of the magnetic bulk susceptibility of Pd_1–x Ag _x with temperature T and silver mole fractionx within 0.5x1 has been investigated in the range 5KT400K. Experimental evidence can be given for an intersection point of the susceptibility isotherms (T=const,x) atx=0.55. The observed dependence of on T andx is interpreted by means of a semiphenomenological alloy susceptibility function (T,x).     

The decays of theρ′1 andω′1 mesons

New measurements of the reactione ⁺ e ^– confirm previous evidence for the decay₁ and provide a strong constraint on the mass of the₁. The results from a detailed analysis of these data are compared with those from a corresponding analysis of new data on the reactione ⁺ e ^–. It is shown that in accord with expectation. This identification of a strong₁ decay supports a previous claim that the₁ and theC(1480), observed in the channel, cannot be different manifestations of the same particle.     

Snake Studies in the HL-1M Tokamak

Lower-hybrid current drive (LHCD) experiments were carried out the HL-1M hydrogen plasmas. The effect of LHCD on central MHD activities [sawtooth (m=0), m =1 mode] were studied with the fluctuations observation of the soft X-ray (SXR) emission.     

Ab initio CI study of the vibrational structure of the 1 1Σ− (1 1 A″)←X and 1 1Δ (2 1 A′, 2 1 A″)←X electronic transitions in HCN and DCN

The results of an ab initio CI study of the vibrational/vibronic structure of the 1 ¹Σ^? (1 ¹ A″)←X and 1 ¹Δ (2 ¹ A′, 2 ¹ A″)←X electronic transitions in HCN and DCN are presented. Calculated band positions and intensity distributions within the band progressions are compared with corresponding experimental data. While the theoretical results for the 1A″←X transition reproduce well the structure of the observed A-X spectrum, they place doubt on the Bickel-Innes interpretation of the B-X band system in terms of transitions to the same excited electronic state but accompanied by excitation of a single quantum of the C?H stretching vibrational mode.     

Contribution of the lowest 1+ intermediate state to the 2νββ-decay amplitude

The half-life with respect to two-neutrino double-beta (2νββ) decay to the final ground state is calculated under the assumption of single-state dominance. To the best of our knowledge, the energy denominators of perturbation theory are considered for the first time without invoking any approximation. The results obtained for the experimentally interesting A=100, 110, 114, 116, and 128 nuclear systems are presented.     

A note on the interpretation ofE 1,E 1+Δ 1 transitions in Ge

The paper deals with problems of the interpretation ofE ₁,E ₁+₁ transitions near 2 eV in Ge. The treatment of ac piezoreflectance spectra of Ge in this energy region shows that the transitionse ₁,E ₁+₁ are, in general, not well-described by any model of the pair of parabolic critical points of the same type; therefore neither of both frequently used models (3DM₁-pair or 2DM₀- pair) is appropriate. The hydrostatic componentW ₁(E) of the piezooptic tensor was extracted from the experimental ac piezoreflectance spectra and then treated by the symmetrization method for the precise determination of transition energies. This method does not depend on the type of the critical points pair and it is based on the existence of a symmetric linear combination of real and imaginary parts of the critical point contribution to the dielectric function.