Update of g-2 of the muon and Δα

We update our Standard Model predictions for g-2 of the muon and for the hadronic contributions （5） 2 to the running of the QED coupling, Δαbad^5）（MZ^2）. Particular emphasis is put on recent changes in the hadronic contributions from new data in the 2π channel and from the energy region just below 2 GeV.     

Update of g-2 of the muon and △α

We update our Standard Model predictions for g-2 of the muon and for the hadronic contributions to the running of the QED coupling,αh(5a)d(MZ2).Particular emphasis is put on recent changes in the hadronic contributions from new data in the 2π channel and from the energy region just below 2 GeV.     

Structure and stability of various states of the EuC and EuC2 molecules

B3LYP level density functional theory （DFT） and multiconfiguration self-consistent-field （MCSCF） level ab initio method calculations have been performed on the basis of relativistic effective core potentials to investigate the nature of EuC and EuC2 molecules. The computed results indicate that the ground states of EuC and EuC2 are ^12∑^＋ and SA2, respectively. Dissociation potential energy curves of the low-lying electronic states of EuC have been calculated using the MCSCF method, and the same level calculation on EuC2 indicates that the dissociation energy of EuC2 of ground state compares well with the available experimental data. The bond characteristic is also discussed using Mulliken populations.     

Elasticity of the B2 phase and the effect of the B1–B2 phase transition on the elasticity of MgO

A study of the high-pressure anisotropy of MgO was conducted using first-principles calculations based on density functional theory within the generalized gradient approximations. The pressure dependence of the elastic stiffness coefficients and the anisotropy parameters, in both B1 and B2 phases, shows that for high-hydrostatic compression the easiest deformation is the shear along (100) plane and the the material's response to deformation and to shearing strains is quite the same. According to the calculations of the velocities of propagation of elastic waves, we deduced that MgO develop an elastic anisotropy, especially, in the B1 phase. We present the B2 phase elastic properties which are not already studied under high pressure.     

High-resolution measurements of the ν2 and 2ν2-ν2 bands of SO2

Infrared measurements have been made on SO₂ between 450 and 602 cm⁻¹ with a resolution of 0.005 cm⁻¹. The B-type bands due to the bending mode transitions 010-000 and 020-010 have been assigned and analyzed for the ³²S¹⁶O₂ molecule. A total of 3007 transitions were measured and fit for ³²S¹⁶O₂ with a standard deviation of 0.0004 cm⁻¹. Ro-vibrational constants are given that fit the current measurements and the pure rotational transitions reported in the literature.     

Observation of the decay Ks → 2γ and measurement of the decay rates KL → 2γ and KS → 2γ

The decay rates of K_L → 2γ and K_S → 2γ have been measured at the CERN SPS. The results are Γ(K_L→2γ)/χ(K_L→2π₀)=0.632±0.004±0.008 and Γ(K_S→2γ)/Γ(K_L→2γ)=2.3 ±1.0±0.4. This is the first observation of K_S→2γ decays.     

Mössbauer study of the quasi-binary sections FeSn2-FeSb2 and FeSn2-FeTe2 of the corresponding ternary systems Fe-Sn-Sb and Fe-Sn-Te

⁵⁷Fe and¹¹⁹Sn Mössbauer and X-ray diffraction studies have been performed at room temperature to establish the presence of various intermediate phases in the quasibinary sections FeSn₂-FeSb₂ and FeSn₂-FeTe₂ {i.e. Fe (Sn_1–xSb_x)₂ and Fe (Sn_1–xTe_x)₂ for 0x1·0 of the respective ternary systems Fe-Sn-Sb and Fe-Sn-Te at 500°C. Using significantly different Mössbauer hyperfine parameters and the X-ray powder diffraction patterns for each existing stable phase, solid solubility limits and presence of single and multiphase regions have been estimated and are reported.     

Status and Plan of the HL-2A Project

HL-2A is a new divertor tokamak under construction at Southwestern Institute of Physics (SWIP), Chengdu, China, based on the experience from HL-1 and HL-1M. HL is the short term of a Chinese word that means “ Toroidal Current Device“ . The main objectives of HL-2A are to produce more adaptable divertor configurations to study energy exhaust and impurity control(the first divertor tokamak plasma in China), and to study enhanced plasma confinement by profile control and moderate plasma shaping.     

Influence of the reagent vibration on the stereo-dynamics of the reactions D^- ＋ H2 and H^- ＋ D2

Employing the quasi-classical trajectory method and the potential energy surface of Panda and Sathyamurhy [Panda A N and Sathyamurthy N 2004 J.Chem.Phys.121 9343],the effect of the reagent vibration on vector correlation of the ion-molecule reactions D～-+H₂ and H～-+D₂ is studied at a collision energy of 35.7 kcal/mol.Four generalized polarization-dependent differential cross sections （2π/σ）（dσ 00 /dωt）,（2π/σ）（dσ 20 /dωt）,（2π/σ）（dσ 22+ /dωt）,and （2π/σ）（dσ 21 /dωt） are presented in the centre-of-mass reference frame,separately.At the same time,the effects on the product angular distributions P （θr）,P （φr） and P （θr,φr） of the title reactions are also analysed.The calculated results show that the scattering tendencies of the product HD,the alignment and the orientation of j sensitively depend on reagent molecule vibration.     

Measurements of air and noble-gas broadening and shift coefficients of the methane R3 triplet of the 2ν3 band

By using a tunable diode laser spectrometer with one absorption White cell for low pressure and one photoacoustic cell for high pressure, line shape parameters of the R3 triplet of the 2ν₃ band of methane at 1.65 μm were measured. The absorption line was recorded by using the wavelength modulation spectroscopy technique with first harmonic detection. The broadening and shift coefficients were obtained by fitting the first harmonic absorption signal while varying the pressure of different perturbing gases: air and noble gases (helium, neon, argon, krypton and xenon). We present here the results for the R3 triplet. The observed shift and broadening coefficients behaviors are discussed. Received: 17 November 2000 / Revised version: 19 February 2001 / Published online: 27 April 2001     

Simultaneous analysis of the ν2 and ν4 bands of methane

Vibration-rotation spectra of the ν₂ and ν₄ bands of CH₄ have been analysed by a simultaneous diagonalization of the hamiltonian matrices for the v ₂=1 and v ₄=1 states coupled by the Bξ_2,4 Coriolis interaction term. The effective hamiltonians used extend to sextic centrifugal distortion terms. The results are a significant improvement on any previous analysis; 438 assigned transitions up to J′=16 have been fitted with an overall standard deviation of 0·016 cm^-1. The method used is compared with an alternative theoretical approach given by Berger.     

Carbon-13 Assignments and Revision of the Stereostructures of the Cadinanes 2-Hydroxy-8α-angeloyloxycalamenene and 2-Hydroxy-8α-hydroxycalamenene

The two known cadinanes 2-hydroxy-8α-hydroxycalamenene and 2-hydroxy-8α-angeloyloxycalamenene were isolated from a Louisiana population of Heterotheca subaxillaris.

Their ¹³C NMR spectra were fully assigned by the application of HETCOR, COLOC, COSY, NOESY and DEPT experiments. It was shown on the basis of NOESY experiments that both cadinanes require revision at the stereogenic centre C-7.     

Status of the lepton g − 2 and effects of hadronic corrections

The electron and muon anomalous magnetic moments (AMM) are measured in experiments and studied in the Standard Model (SM) with the highest precision accessible in particle physics. The comparison of the measured quantity with the SM prediction for the electron AMM provides the best determination of the fine structure constant. The muon AMM is more sensitive to the appearance of New Physics effects and, at present, there appears to be a three- to four-standard deviation between the SM and experiment. The lepton AMMs are pure relativistic quantum correction effects and therefore test the foundations of relativistic quantum field theory in general, and of quantum electrodynamics (QED) and SM in particular, with highest sensitivity. Special attention is paid to the studies of the hadronic contributions to the muon AMM which constitute the main source of theoretical uncertainties of the SM.     

Phase Transition in Ag2S and the Relative Position of Atomic Planes of the α-Ag2S and β-Ag2S Phases

JETP Letters - The relative position of atomic planes of low-temperature monoclinic acanthite α-Ag2S and high-temperature bcc argentite β-Ag2S has been determined from X-ray and electron...     

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.     

Assignments of the 13C NMR Spectra of Enhydrin and 2′,3′-Dehydromelnerin A and the Molecular Structure of Enhydrin

Abstract

Two melampolide-type sesquiterpene lactones, enhydrin and 2,′ 3′-dehydromelnerin A, were isolated from a Louisiana population of Polymnia uvedalia. Their ¹³C NMR spectra were assigned using ¹³C-¹H correlation, DEPT and COLOC experiments. The molecular structure of enhydrin was established by single crystal X-ray diffraction.     

Special Features of the Correlation between the Uranium–Oxygen Interatomic Distances and the Frequencies of the Valence Vibrations of the UO2 2+ Group in Complex Compounds of Uranyl

We considered the factors due to which the dependences between the uranium–oxygen distances R ₀ and the frequencies of valence vibrations _as for complex compounds of uranyl are described by two independent expressions generally represented by equations of the type R ₀ = a + b_as ^–2/3 (b > 0) with the coefficients a and b differing in the regions R ₀ < 0.178 nm and R ₀ > 0.178 nm. It is shown that the reason is that there is a mutual effect of the ligands in the uranyl complex responsible for different partial contributions of the uranium orbitals and of the atoms of the first coordination sphere to the chemical bonding.     

Calculation of vibrations of the H-bonds and electrooptical parameters of the F(HF)2]− complex

The problem of calculating the vibrations of the F(HF)₂]^? complex with hydrogen bonds is considered with allowance for the anharmonicity and interaction of motions in different degrees of freedom. A systematic solution of this problem is proposed which consists in separating the total vibrational system into subsystems, obtaining sufficiently exact vibrational wave functions of subsystems, and expanding the vibrational wave functions of the total system in basis functions constructed from the wave functions of subsystems. At the first stage of our study, the stretching and bending modes of two F...HF hydrogen bonds are considered with the use of an exact kinetic energy operator and a nonempirical three-dimensional potential energy surface. It is shown that these vibrational modes of the complex are characterized by significant mechanical and electric anharmonicities. The calculated values of frequencies of the symmetric and antisymmetric vibrations of hydrogen bonds are in good agreement with the experimental findings.     

Development and Application of the 2D Relativistic Fokker-Planck Package

The Fokker Planck package which without the relativity effect has been developed in 2002. The package with relativity effect, which induced from Italy, is now developed. It conrains relativity effect, and is bounce averaged. It can deal with such as the trapping effect, wave heating, neutral beam injecting, and particle losses. It is very useful for our HL-2A experimental results analysis.