Inclusive production of baryons in decays of the γ (9.46) and in quark jets

Inclusive Production of mesons and baryons in quark jets at \(\sqrt s = 9.5 \ldots 36GeV\) and in decays of the γ(9.46) meson has been studied using the Quark Recombination Model (QRM). The model predictions for quark jets agree with data. The QRM-simulation of three-gluon decays of the γ(9.46) shows an enhancement of the inclusive baryon rate, as was observed recently by the DASP II experiment.     

Study of ψ(4415) in the QPC model

Some authors consider the ψ(4415) to be the 4S or 5S excited tate of a cc pair. Starting from this assumption, we study he decays of the ψ(4415) to DD, D^*D^*, D_SD_S, D_S^*D_S^*, and get the corresponding branching ratios in terms of the Quark-Pair-Creation (QPC) model. Compared with the experimental data, we find that the results of 4S state agree much better than those of the 5S state. Therefore, it is more reasonable to assume the ψ(4415) to be a 4S state.     

Observation of negative photoconductivity in (ZnO)x(CdO)1−x films

In this study, (ZnO)_x(CdO)_1?x films were prepared by ultrasonic spray pyrolysis (USP) technique at a substrate temperature of 400 °C. X-ray diffraction patterns of the films indicate that the (ZnO)_x(CdO)_1?x films have hexagonal wurtzite and cubic structure for the constituent materials. A decrease in the average transmission with increasing quantity of the cadmium acetate dehydrate in the sprayed solution was observed. The photoconductivity transients were performed using UV light, which has 360 nm wavelength. After light cut off, conductivity changed slowly, and the decay time was thousands of seconds. The films with x=0.2 and 0 exhibited negative photoconductivity. Temperature-dependent photoconductivity and dark conductivity measurements were performed and negative photoconductivity was also observed for the same films (x=0.2 and 0). Photoluminescence measurements were performed and band-to-band excitation energies of (ZnO)_x(CdO)_1?x films were determined. Band gap of the pure CdO film was found as 3.11 eV, interestingly.     

The Spectrochemical Properties of bis-(α-Methioninephosphonato)Copper(II) in Aqueous Solution

The combined results of spectrophotometric measurements and e.s.r. spectra, as well as those obtained from potentiometric titration studies, are used to determine the structure of the individual complex species formed between copper(II) ion and 1-amino-3-methylthiopropane-phosphonic acid (α-MetP) in aqueous solution. The e.s.r. parameters are typical for CuN₂O₂ coordination geometries. The d-d absorption spectrum of [Cu(α-MetP)₂]^2-chromofore in aqueous solution has been treated by the Angular Overlap Model in C_2h, symmetry. Low-symmetry splittings of the broad asymmetric absorption band in the measured spectrum were found by Gaussian analysis. The effect of the σ-and π-bonding of bidentate ligand upon the central ion d-orbital energies is destribed in a ligand-field framework.     

Spectroscopic and laser properties of Nd~(3 ) ions in LaMgAl_(11)O_(19) crystals

The spectroscopic properties, optic quality and thermal lensing effect of Nd~(3 ) ions in LaMgAl_(11)O_(19)(LNA) crystals are investigated and the dependence of the laser characteristics on above properties are discussed.     

Photodynamics of Ga_(Zn)–V_(Zn) complex defect in Ga-doped ZnO

The wide-band-gap II–VI compound semiconductor ZnO is regarded as a promising single-photon emission(SPE)host material. In this work, we demonstrate that a(GaZn–VZn)-complex defect can readily be obtained and the density can be controlled in a certain range. In analogy to nitrogen vacancy centers, such a defect in ZnO is expected to be a new single photon source. The optical properties of the(GaZn–VZn)-complex defect are further studied by photoluminescence and time-resolved photoluminescence spectra measurements. The electron transitions between the defect levels emit light at ～ 650 nm with a lifetime of 10–20 nanoseconds, indicating a good coherent length for SPE. Finally, a two-level emitter structure is proposed to explain the carrier dynamics. We believe that the photodynamics study of the(GaZn–VZn)-complex defect in this work is important for ZnO-based quantum emitters.     

Realization of a SU(2)×SU(6) system of fermions in a cold atomic gas

We report the realization of a novel degenerate Fermi mixture with an SU(2)×SU(6) symmetry in a cold atomic gas. We successfully cool the mixture of the two fermionic isotopes of ytterbium 171Yb with the nuclear spin I=1/2 and 173Yb with I=5/2 below the Fermi temperature T_{F} as 0.46TF for 171Yb and 0.54TF for 173Yb. The same scattering lengths for different spin components make this mixture featured with the novel SU(2)×SU(6) symmetry. The nuclear spin components are separately imaged by exploiting an optical Stern-Gerlach effect. In addition, the mixture is loaded into a 3D optical lattice to implement the SU(2)×SU(6) Hubbard model. This mixture will open the door to the study of novel quantum phases such as a spinor Bardeen-Cooper-Schrieffer-like fermionic superfluid.     

Study on Production of Exotic 0 Meson D*sJ(2317) in Decays of ψ(4415)

The newly observed D*sJ family containing D*sJ(2317), DsJ(2460), and DsJ(2632) attracts great interests.Determining their structures may be an important task for both theorists and experimentalists. In this work we use a non-relativistic model (the harmonic oscillator model) to evaluate the production rate of D*sJ (2317) from the decays of ψ(4415). For a comparison, we also employ the widely adopted heavy quark effective theory to repeat the calculation.We find that the rate is sizable and may be observed at BES Ⅲ and CLEO, if it is a p-wave excited state of Ds (1968).Unfortunately, the other two members of the family cannot be observed through decays of charmonia, because of the constraints from the final state phase space.     

Increase in the coercivity of an ensemble of (DyPr)–(CoFe)–B microparticles during their dispersion in a polymer matrix

In ensembles of annealed ferrimagnetic alloy (DyPr)–(CoFe)–B microparticles in the free state and fixed in polymer, the coercivity differs more than by an order of magnitude. The contributions of orientation locking of magnetic axes of particles and the dipole magnetic interaction between particles to the coercivity and saturation magnetization field of an ensemble are discussed. In ensembles of unannealed microparticles, the effect of their locking and dispersing in polymer is significantly weaker.     

The Structure of S Pair in Collective States (Ⅰ)

A new S pair and seniority particle operator used to overcome the difficulties due to seniority mixing are defined in collective motion of nuclei. The structure amplitude of S pair is determined in a self-consistent manner.     

The Structure of S Pair in Collective States (Ⅱ)

Comparison between states composed of the newly defined S pairs used for dealing with seniority mixing problem and those made from the usual S pairs is given.     

Quasiparticle structure of superheavy nuclei in α-decay chains of ~(285)Fl and ~(291,293)Lv

Two mean-field potentials, Woods-Saxon and Skyrme based potentials, are used to calculate the energies of low-lying one-quasiparticle states. The spectra of the low-lying states and the α-decay spectra of nuclei belonging to the α-decay chains of ~(285)Fl and ~(291,293)Lv are calculated and compared with the available experimental data. Dependence of the splitting of the pseudospin doublets and of the energies of the unique parity neutron one-quasiparticle states on the mean field potential are discussed. As shown, the α-decay spectra could be different in the α-decay chain and at the direct production of the nucleus in a fusion reaction.     

Thermodynamic modelling of miscibility in (InAs) x (GaAs)1−x solid solutions

Current methods used to model the solution thermodynamics of III–V compound semiconductors involve the use of the valence force field as the molecular model and the regular solution model (with the temperature independent interaction parameter and underlying assumption of random mixing) as the engineering model. In this study, excess free energy models (with three or less adjustable parameters) are investigated to predict the solid–solid miscibility of (InAs) _x (GaAs)_{1? x} . The models investigated include the Porter/one-constant Margules (OCM) model, the two-constant Margules (TCM) model and the non-random two liquid (NRTL) model. These models are fit to excess free energy values derived from free energy change of mixing (variation with composition) data available from molecular simulations at different temperatures. The parameters in all the models have been found to be temperature dependent. The coexistence compositions are best predicted by the NRTL model, indicating the need to consider non-random mixing effects present in these solid solutions. The TCM model predicts better equilibrium composition data as compared to the OCM model.     

Possible effects of oxygen in Te-rich Σ3 (112) grain boundaries in CdTe

Using density functional theory calculation, we show that oxygen (O) exhibits an interesting effect in CdTe. The Te atoms with dangling bonds in a Te-rich rich Σ3 (112) grain boundary (GB) create deep gap states due to strong interaction between Te atoms. However, when such a Te atom is substituted by an O atom, the deep gap states can be shifted toward the valence band, making the site no longer a harmful non-radiative recombination center. We find that O atoms prefer energetically substituting these Te atoms and induce significant lattice relaxation due to their smaller atomic size and stronger electronegativity, which effectively reduces the anion–anion interaction. Consequently, the deep gap states are shifted to lower energy regions close to or even below the top of the valence band.     

Infinite Number of Integrals of Motion in Classically Integrable System With Boundary (Ⅱ)

In Affine Toda field theory, links among three generating functions for integrals of motion derived from P. (Ⅰ) are studied, and some classically integrable boundary conditions are obtained. An infinite number of integrals of motion are calculated in ZMS model with quasi-periodic condition. We find the classically integrable boundary conditions and K± matrices of ZMS model with independent boundary conditions on each end. It is identified that an infinite number of integrals of motion does exist and one of them is the Hamiltonian, so this system is completely integrable.     

Selected applications of perturbed angular correlation of γ-rays (PAC) spectroscopy in biochemistry

PAC spectroscopy was first applied in biochemistry more than 40 years ago in a study of serum albumin (Leipert et al., Nature 220:907–909, 1968). Over the following decades a number of such applications have appeared in the literature, demonstrating that PAC spectroscopy is a useful tool in the study of biomolecules. Selected prototypical examples with ^111mCd, ¹¹¹Ag, and ^199mHg are presented in this work with a particular focus on the biological role of metal ions in catalysis, protein structure and function, protein–protein interaction in biochemical reaction paths, in vivo binding of mercury ions to barley, and the use of de novo designed proteins to systematically explore the interaction of proteins and metal ions.     

Polarization properties of baryons in the hadronic decays of the Δ(1232) resonance

The angular distribution of the probability for the Δ(1232)-resonance decay Δ(1232) → Nπ versus the polarizations of baryons and the vector of dynamical nucleon polarization are calculated.     

A class of solutions in the O(3) σ-model

In a recent paper Chelnokov and Zeitlin obtained a set of differential equations for the O(3) σ-model in euclidean space and solved it under some assumption. Similar equations were obtained by Popov and Zeitlin for a ³He film and solved it under another assumption. The present note generalises the solutions obtained by these two assumptions.     

Structure of σ model in [1, 1] representation of SU(2) ⊗ SU(2) group

The spontaneous breakdown of symmetry of the-model in the [1, 1] representation of SU(2) SU(2) group is investigated. It is shown that the spontaneous breakdown is realized in all cases of squared mass ² in mass term in the Lagrangian ( ²>0, ²=0, ²<0), unlike the-model in [1/2, 1/2] representation, in which the spontaneous breakdown only for the case ²<0 manifests itself. Further, different but equivalent methods of obtaining the nonlinear realization for pions in the frame of an extended in such a way-model are demonstrated. Finally, it is sketched, that the obtained results can be generalized to all [N/2,N/2] representations of SU(2) SU(2) chiral group.Presented at the Symposium on Hadron-Hadron Scattering at High Energies, Liblice, Czechoslovakia, June 16–21, 1975.On leave of absence from theDept. of Theoretical Physics, Comenius University, Bratislava, Czechoslovakia.