Diverse <Emphasis Type="Italic">N</Emphasis>=(4,4) Twisted Multiplets in the <Emphasis Type="Italic">N</Emphasis>=(2,2) Superspace

We describe four different types of N=(4, 4) twisted supermultiplets in the two-dimensional N=(2, 2) superspace ℝ^(1,1|2,2). All these multiplets are represented by a pair of chiral and twisted chiral superfields and differ in the transformation properties under an extra hidden N=(2, 2) supersymmetry. The sigma-model N=(2, 2) superfield Lagrangians for each type of the N=(4, 4) twisted supermultiplet are real functions subjected to some differential constraints implied by the hidden supersymmetry. We prove that the general sigma-model action including all types of N=(4, 4) twisted multiplets and invariant under the N=(4, 4) supersymmetry reduces to a sum of sigma-model actions for separate types. An interaction between the multiplets of different sorts is possible only through the appropriate mass terms and only for those multiplets that belong to the same “self-dual” pair. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 145, No. 1, pp. 66–86, October, 2005.     

B→KK衰变中的软胶子修正

应用光维QCD求和规则研究了B→KK衰变的软胶子交换修正,虽然QCD因子化方法已经计算了领头阶的因子化和硬胶子交换的α_s阶辐射修正部分,然而系统地估算所有树图和企鹅图的非因子化软胶子贡献是有价值的,我们的结果表明在B→KK衰变中软胶子效应总是使分支比值减小,约为几个百分点.     

Chiral effective Lagrangian for excited heavy-light mesons from QCD

We derive the chiral effective Lagrangian for excited heavy-light mesons from QCD under proper approximations. We focus on the chiral partners with j_l~P=3+/2 and j_l~P=3~-/2 which amounts to(1~+, 2~+) and(1~-, 2~-) states respectively. The low energy constants including the masses of the chiral partners are calculated. The calculated spectrum for the excited mesons are found roughly consistent with experimental data. In addition, our results indicate that quantum numbers of B_J(5970) can be identified with 1~-or 2~-.     

Asymptotic behaviour of viscoelastic composites with almost periodic microstructures

In this paper, we study the acoustic properties of porous media saturated by an incompressible viscoelastic fluid. The model considered here consists of a linear deformable porous skeleton having memory that is surrounded by a viscoelastic Oldroyd fluid. Assuming the microstructures to be almost periodically distributed and under the almost periodicity hypothesis on the coefficients of the governing equations, we determine the macroscopic equivalent medium. To achieve our goal, we use some very recent tools about the sigma convergence of convolution sequences. Copyright © 2017 John Wiley & Sons, Ltd.     

Revisiting D-meson twist-2, 3 distribution amplitudes

Owing to the significant difference between the experimental measurements and the theoretical predictions of the standard model (SM) for the value of \begin{document}$ {\cal{R}}(D) $\end{document} of the semileptonic decay \begin{document}$ B\to D\ell\bar{\nu}_{\ell} $\end{document}, researchers speculate that this decay may be evidence of new physics beyond the SM. Usually, the D-meson twist-2, 3 distribution amplitudes (DAs) \begin{document}$ \phi_{2;D}(x,\mu) $\end{document}, \begin{document}$ \phi_{3;D}^p(x,\mu) $\end{document} , and \begin{document}$ \phi_{3;D}^\sigma(x,\mu) $\end{document} are the main error sources when perturbative QCD factorization and light-cone QCD sum rules are used to study \begin{document}$ B\to D\ell\bar{\nu}_{\ell} $\end{document}. Therefore, it is important to obtain more reasonable and accurate behaviors for these DAs. Motivated by our previous work [Phys. Rev. D 104, no.1, 016021 (2021)] on pionic leading-twist DA, we revisit D-meson twist-2, 3 DAs \begin{document}$ \phi_{2;D}(x,\mu) $\end{document}, \begin{document}$ \phi_{3;D}^p(x,\mu) $\end{document}, and \begin{document}$ \phi_{3;D}^\sigma(x,\mu) $\end{document}. New sum rule formulae for the \begin{document}$\xi $\end{document}-moments of these three DAs are suggested for obtaining more accurate values. The light-cone harmonic oscillator models for the DAs are improved, and their parameters are determined by fitting the values of ξ-moments via the least squares method.     

D0(D-)0 mixing and other recent charm results from BABAR

Studies in which BABAR data have shown evidence for mixing in the neutral charm meson system are presented.A new measurement of the lifetime difference parameter yCP=(1.16±0.22±0.18)% is described.Results are also presented from a systematic study of DK and D*K invariant mass distributions from a 470 fb-1sample of asymmetric e+e-interactions recorded by the BABAR detector at the PEP-Ⅱ storage rings.A new charmed-strange meson has been observed with mass[3044±8stat(+30-5)syst]MeV/c2 and width[239±35stat(+46-42)syst]MeV/c2.     

Transverse momentum dependence of differential directed flow of Λ hyperon within kaon covariant dynamics

The transverse momentum distributions of Λ's and proton's directed flows are investigated by using Quantum Molecular Dynamics model (QMD) within the framework of covariant kaon dynamics. The calculated results show that the transverse momentum distribution of differential directed flow of Lambda hyperons is dependent appreciably on the nuclear matter equation of states (EOS). The differential directed flow of Lambda hyperons calculated with soft EOS is consistent with the experimental data,whereas the discr...     

B→K0^＊（1430）K Decays in Perturbative QCD Approach

In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.     

Linear free energy relationships of half-wave reduction potentials of (E)-4-aryl-4-oxo-2-butenoic acids

Half-wave reduction potentials of a set of twelve (E)-4-aryl-4-oxo-2-butenoic acids obtained by direct current polarography in methanol are reported. E_1/2 is correlated with Hammett sigma values as well as with values of frontier molecular orbitals calculated at a semiempirical molecular orbital level. Constant potential electrolysis of a representative compound shows that the first polarographic wave corresponds to one-electron reduction. The isolation of the product proves reduction of the activated double bond.