Final-state polarization in <Emphasis Type="Italic">B</Emphasis><Stack><Subscript><Emphasis Type="Italic">s</Emphasis></Subscript><Superscript>0</Superscript></Stack> decays

Certain B _s ⁰→V ₁ V ₂ decays (V _i is a vector meson) can be related by flavor SU(3) symmetry to corresponding B _d ⁰→V ₃ V ₄ decays. In this paper, we show that the final-state polarization can be predicted in the B _s ⁰ decay, assuming polarization measurements of the B _d ⁰ decay. This can be done within the scenario of penguin annihilation (PA), which has been suggested as an explanation of the unexpectedly large transverse polarization in B→φ K ^*. PA is used to estimate the breaking of flavor SU(3) symmetry in pairs of decays. Two of these for which PA makes a reasonably precise prediction of the size of SU(3) breaking are (B _s ⁰→φ φ,B _d ⁰→φ K ^0*) and ( ). The polarization measurement in the B _d ⁰ decay can be used to predict the transverse polarization in the B _s ⁰ decay and will allow for testing of PA as well as the other assumptions in the analysis.     

Mixing of <Emphasis Type="Italic">K</Emphasis><Superscript>0</Superscript> and <Emphasis Type="Italic">B</Emphasis><Superscript>0</Superscript> neutral mesons within the minimum supersymmetry model

Mixing of K ⁰ and B ⁰ mesons is studied in the scope of the minimum supersymmetry model (MSSM) with a type II Yukawa sector and explicit violation of CP invariance in the Higgs potential. The mixing parameters Δm _LS and ? are calculated in the limit of the low-energy four-fermion approximation with a charged Higgs boson exchange. It is shown that supersymmetric effects are very small for K ⁰ mesons and may be quite significant for B _s ⁰ and B _d ⁰ mesons, which imposes constraints on the MSSM parameter space.     

<Emphasis Type="Italic">B</Emphasis> and <Emphasis Type="Italic">B</Emphasis><Subscript><Emphasis Type="Italic">s</Emphasis></Subscript> decay constants from moments of finite energy sum rules in QCD

We use an appropriate combination of moments of finite energy sum rules in QCD in order to compute the B _q -meson decay constants f _B and . We perform the calculation using a two-loop computation of the imaginary part of the pseudoscalar two point function in terms of the running bottom quark mass. The results are stable against the so-called QCD duality threshold, and they are in agreement with the estimates obtained from Borel transform QCD sum rules and lattice computations.Received: 28 July 2004, Revised: 10 September 2004, Published online: 23 November 2004PACS: 12.38.Bx, 12.38.LgSupported by MCYT-FEDER under contract FPA2002-00612.     

<Emphasis Type="Italic">B</Emphasis><Stack><Subscript>s</Subscript><Superscript>0</Superscript></Stack> physics at LHCb

The LHCb experiment is in preparation, to be ready for the start of the LHC. The physics which will be performed by LHCb is reviewed, focussing on what can be learnt fromB _s ⁰ mesons.     

The <Emphasis Type="Italic">N</Emphasis> = 2 Heavenly Equation

This paper presents report of the joint work with Z. Popowicz, which appeared in J. Phys. A, concerning the construction of a manifestly N = 2 supersymmetric heavenly equation in 2 + 1 dimensions. Its integrability properties have been derived from an N = 2 supersymmetric Lax pair, based on the n limit of the sl(n;n + 1) superalgebra series. The superhydrodynamical type of restrictions to 1+1 dimensions have been analyzed.     

Spectroscopy and Regge trajectories of heavy quarkonia and <Emphasis Type="Italic">B</Emphasis><Subscript><Emphasis Type="Italic">c</Emphasis></Subscript> mesons

The mass spectra of charmonia, bottomonia and B _c mesons are calculated in the framework of the QCD-motivated relativistic quark model based on the quasipotential approach. The dynamics of heavy quarks and antiquarks is treated fully relativistically without application of the nonrelativistic v ²/c ² expansion. The known one-loop radiative corrections to the heavy quark potential are taken into account perturbatively. The heavy quarkonium masses are calculated up to rather high orbital and radial excitations (L=5, n _r =5). On this basis the Regge trajectories are constructed both in the total angular momentum J and radial quantum number n _r . It is found that the daughter trajectories are almost linear and parallel, while parent trajectories exhibit some nonlinearity in the low mass region. Such nonlinearity is most pronounced for bottomonia and is only marginal for charmonia. The obtained results are compared with the available experimental data, and a possible interpretation of the new charmonium-like states above open charm production threshold is discussed.     

<Emphasis Type="Italic">N</Emphasis> = 1, 2 supersymmetric non-local gas equation

In this paper we study the supersymmetrization of the N = 1 and N = 2 nonlocal gas equation. We show that this system is bi-Hamiltonian. While the N = 1 supersymmetrization allows the hierarchy of equations to be extended to negative orders (local equations), we argue that this is not the case for the N = 2 supersymmetrization. In the bosonic limit, however, the N = 2 system of equations lead to a new coupled integrable system of equations. Presented at the International Colloquium “Integrable Systems and Quantum Symmetries”, Prague, 16–18 June 2005.     

Effects of minimal supersymmetry standard model in neutral <Emphasis Type="Italic">K</Emphasis><Superscript>0</Superscript> meson mixing

Mixing of neutral K ⁰ mesons is studied in the framework of the minimal supersymmetric model (MSSM) with a Yukawa type II sector and explicit violation of CP invariance in the Higgs potential. Mixing parameters Δm _LS and ɛ are calculated in the limit of the four-fermion approximation with charged Higgs boson exchange. This work specifies the data presented in [1] more precisely and, taking into account the influence of new contributions on the above observables, proves the small degree of supersymmetric effects for a system of K ⁰ mesons.     

The excitation cross section of cadmium atoms from metastable 5<Emphasis Type="Italic">s</Emphasis>5<Emphasis Type="Italic">p</Emphasis><Superscript>3</Superscript><Emphasis Type="Italic">P</Emphasis><Subscript>0, 2</Subscript> states by electron impact

By means of the optical method using the technique of crossed electron and atomic beams, we obtained the absolute values of the excitation cross sections of metastable cadmium atoms and their energy dependences. The absolute cross section values reach ∼10⁻¹⁶ cm² (at 30 eV). Sharp resonance-like maxima are observed in the energy dependences of the excitation cross section near the excitation thresholds, which are supposedly related to the formation and decay of negative-ion excited states of.     

<Emphasis Type="Italic">B</Emphasis><Subscript><Emphasis Type="Italic">c</Emphasis></Subscript> meson rare decays in the light-cone quark model

We investigate the rare decays \(B_{c} \rightarrow D_{s}(1968)\ell \overline{\ell}\) and \(B_{c}\rightarrow D_{s}^{*}(2317) \ell \overline{\ell}\) in the framework of the light-cone quark model (LCQM). The transition form factors are calculated in the space-like region and then analytically continued to the time-like region via exponential parametrization. The branching ratios and longitudinal lepton polarization asymmetries (LPAs) for the two decays are given and compared with each other. The results are helpful for investigating the structure of B _c meson and for testing the unitarity of CKM quark mixing matrix. All these results can be tested in the future experiments at the LHC.     

Evidence for formation of a narrow <Emphasis Type="Italic">K</Emphasis><Stack><Subscript>S</Subscript><Superscript>0</Superscript></Stack><Emphasis Type="Italic">p</Emphasis> resonance with mass near 1533 MeV in neutrino interactions

A narrow baryon resonance is observed in the invariant mass of the K _S ⁰ p system formed in neutrino and antineutrino collisions with nuclei. The mass of the resonance is estimated at 1533±5 MeV. The observed width is less than 20 MeV and is compatible with being entirely due to experimental resolution. The statistical significance of the signal is near 6.7 standard deviations. Since the position of the observed resonance does not match the mass of any known Σ*⁺ states, we believe that it arises from the neutrino production of the Θ⁺ pentaquark baryon. The analysis is based on the data obtained in past neutrino experiments with big bubble chambers: WA21, WA25, WA59, E180, and E632.     

<Emphasis Type="Italic">B</Emphasis><Subscript><Emphasis Type="Italic">K</Emphasis></Subscript> from the lattice with Wilson quarks

We report our results for the bag parameter B _K obtained from the quenched simulations on the lattice with Wilson fermions for three values of the lattice spacing. We implemented the method by which no subtraction of the mixing with other four-fermion operators is needed. Our final result, in terms of the renormalization group invariant bag parameter, is .Received: 9 July 2004, Revised: 27 July 2004, Published online: 21 September 2004     

Study of the formation and unimolecular fragmentation of Si<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>O<Stack><Subscript><Emphasis Type="Italic">m</Emphasis></Subscript><Superscript>+</Superscript></Stack> clusters under ion bombardment

The dependences of the emission and fragmentation of clusters sputtered by Xe⁺ ions from the surface of Si _n O _m ⁺ on the oxygen pressure near the bombarded surface are studied using secondary ion mass spectrometry. It is shown that the process of Si _n O _m ⁺ cluster formation under ion bombardment can be described within the framework of the mechanism of combinatorial synthesis by taking into account the mutual reversibility of the reactions of formation and unimolecular decay.     

Fragmentation of sputtered Si<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>O<Stack><Subscript><Emphasis Type="Italic">m</Emphasis></Subscript><Superscript>+</Superscript></Stack> clusters: Release kinetic and dissociation energies

The spectra of kinetic energies of positive Si _n O _m ⁺ cluster ions (n = 2–5, m = 2–7) have been measured using a double focusing ion microanalyzer with reverse geometry at instants 10⁻⁵ to 10⁻⁴ s after emission. The dissociation energies have been determined within the evaporative ensemble model and the theory of unimolecular decay reactions. The results obtained are compared with the binding energies of neutral Si _n O _m clusters.     

Vertex functions for the three-particle interaction of the Higgs bosons <Emphasis Type="Italic">h</Emphasis><Superscript>0</Superscript> and <Emphasis Type="Italic">H</Emphasis><Superscript>0</Superscript> in the minimal supersymmetric standard model: One-loop analysis

Within the minimal supersymmetric standard model, two vertex functions for the three-particle interaction of the neutral Higgs bosons h⁰ and H⁰ are analyzed in the one-loop approximation with allowance for a complete set of one-loop diagrams. The analysis is performed in the c.m. frame under the assumption that one of the Higgs bosons is virtual. The results obtained in this way are compared with those that involve only leading corrections in the low-energy approximation. The vertex functions in question are presented graphically versus the mixing angle β and the energy \(\sqrt s\). It is shown that corrections to these vertex functions may be significant in some domain of the model-parameter space, so that they must be taken into account in performing a detailed analysis of experimental data and theoretical predictions. The possibility of experimentally observing the dependences under study is explored.     

Electronic structure of crystal-forming fulborenes B<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>N<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>

A general approach is formulated to the design of crystal-forming fullerene-like clusters X _n Y _n from which zeolite-like covalent crystals based on IV-IV, III-V, and II-VI binary semiconductor compounds with diamond-like sp ³ bonds can be constructed and synthesized by means of copolymerization through faces. A number of the smallest sized crystal-forming boron nitride clusters are constructed, such as the B₁₂N₁₂, B₁₆N1₆, B₁₈N₁₈, B₂₄N₂₄, B₃₆N₃₆, and B ₆₀N₆₀ fulborenes. The optimized configurations, electronic structures, charge transfers, band gaps, total energies, cohesive energies, and electron density maps of the clusters are calculated using the spin-restricted Hartree-Fock method in the 6–31G basis set. Comparative calculations of the B₆₀N₆₀ fulborene with the use of the density functional theory method have demonstrated that the spin-restricted Hartree-Fock method in the 6–31G basis set is optimum from the standpoint of the accuracy and efficiency.     

Multiple two-variable <Emphasis Type="Italic">p</Emphasis>-adic <Emphasis Type="Italic">q-L</Emphasis>-function and its behavior at <Emphasis Type="Italic">s</Emphasis> = 0

The objective of this paper is to construct a multiple p-adic q-L-function of two variables which interpolates multiple generalized q-Bernoulli polynomials. By using this function, we solve a question of Kim and Cho. We also define a multiple partial q-zeta function which is related to the multiple q-L-function of two variables. Finally, we give a finite-sum representation of the multiple p-adic q-L-function of two variables and prove a multiple q-extension of the generalized formula of Diamond and Ferrero-Greenberg.     

Discrete breathers in biatomic crystals of <Emphasis Type="Italic">AB</Emphasis> and <Emphasis Type="Italic">A</Emphasis><Subscript>3</Subscript><Emphasis Type="Italic">B</Emphasis> composition

The conditions for the existence of discrete breathers (DBs) in biatomic crystals of AB and A ₃ B composition are established, and their properties are studied by means of molecular mechanics using the examples of CuAu and Pt₃Al, respectively. The phonon spectra of the crystals are analyzed, and a gap in the phonon spectrum of CuAu is obtained via considerable homogeneous elastic strain. There is a gap in the phonon spectrum of the Pt₃Al crystal at zero strain, due to the considerable difference between the atomic weights of its components. The frequencies at which discrete breathers can exist in the considered crystals are determined. The energy localized on different types of DBs is estimated. The propagation of a current pulse through Pt₃Al resulting in the excitation of DBs with mild nonlinearity is simulated.     

Two-photon decays of neutral <Emphasis Type="Italic">B</Emphasis> mesons within a model featuring one universal extra dimension

Contributions to the B _s(d) → γγ decay amplitude beyond the Standard Model are estimated within a model featuring one universal extra dimension. It is found that these additional contributions may amount to 6 or 7% of the branching ratios evaluated within the Standard Model.     

Polynomial Realization of <Emphasis Type="Italic">s</Emphasis>l<Subscript><Emphasis Type="Italic">q</Emphasis></Subscript>(2) and Fusion Rules at Exceptional Values of <Emphasis Type="Italic">q</Emphasis>

Representations of the sℓ_q(2) algebra are constructed in the space of polynomials of real (complex) variable for q^N=1. The spin addition rule based on eigenvalues of Casimir operator is illustrated on few simplest cases and conjecture for general case is formulated.