Mesons of the f0 family in processes ππ↦ππ, K¯K up to 2 GeV and the chiral-symmetry breaking

In a combined analysis of the experimental data on the coupled processes ππ↦ππ, KˉK in the channel with I ^G J ^PC = 0⁺0^{+ +}, the various scenarios of these reactions (with different numbers of resonances) are considered. In a model-independent approach, based only on analyticity and unitarity, a resonance is represented by a pole cluster (poles on the Riemann surface) of the definite type that is defined by the state nature. The best scenario contains the resonances f ₀(665) (with properties of the σ-meson), f ₀(980) (with a dominant sˉs component), f ₀(1500) (with a dominant flavour-singlet, e.g., glueball component) and the f ₀(1710) (with a considerable sˉs component). If the f ₀(1370) exists, it has a dominant sˉs component. The coupling constants of the observed states with the considered channels and the ππ and KˉK scattering lengths are obtained. The conclusion on the linear realization of chiral symmetry is drawn. Received: 25 April 2002 / Accepted: 4 June 2002 / Published online: 26 November 2002 RID="a" ID="a"e-mail: surovcev@thsun1.jinr.ru RID="b" ID="b"e-mail: krupa@savba.sk RID="c" ID="c"e-mail: fyzinami@nic.savba.sk Communicated by V.V. Anisovich     

关于标量介子的研究

基于a₀(980)和D^*_sJ(2317)属于1 ³P₀介子多重态这个主要假定, 在准线性Regge轨迹方案下估计了1 ³P₀介子多重态成员的质量. 在介子-介子混合的框架下,建议a₀(980), K^*₀(1052), f₀(1099)和f₀(530)组成基态标量介子九重态, 并且f₀(1099)主要由ss组成,而f₀(530)主要是uu+dd. 这些态可能分别对应已观察到的标量态a₀(980), κ(900), f₀(980)和f₀(600)/σ. 另外, 在胶球为主的图像下, 估计基态标量胶球的质量大约为1340MeV. 给出的结果与其他不同方法给出的结果是一致的.     

空间羣算符的矩阵元

本文首先通过对波失星直接乘积的分析指出,如果 ^*K″∈^*K?^*K′,则波矢峯G_k″可以有下面四种情况:A)G_k同G_k′,是G_k″的子峯,B)G_k=G_k′=G_k″,C)G_k″=G_s, D)G_s是G_k″的子峯。根据上述四种情况,分别考虑积分A=μ″^i″(k″)|f_μⁱ(k)|f_μ′^i′(k′)>的简约。并且证明,对所有四种情况,积分A的值均可由短阵U的矩阵元统一地表达出来。矩阵U是使可约表示Г′简约的转换矩阵,对四种情况,可约表示Г′分别是:A)(Г_kⁱ?Г_k′^i′)^(?),B)Гⁱ?Г_k′^i′,C)Г_k^i(s)?Г_k′^i′(s),D)(Г_k^i(s)?Г_k′^i′(s))^(?)。最后,利用准投影算符的方法,对矩阵U进行了计算,导出空间峯Wigner-Eckart定理的表式。     

无定形靶中离子注入的R,Rp,△Rp的理论计算

本文在Thomas-Fermi势能基础上,导出了全射程R的解析解:R=2/a[E^1/2-A₁(arctg(2E^1/2-f)/△^1/2+arctg f/△^1/2)+B₁ln((E^1/2-f)²)/(E-fE^1/2+d) ·d/f²],其中A₁,B₁,f,d和△均为与离子及靶的质量、原子序数有关的常数。结合导出的η=R/(R_p)(R_p指投影射程)比值的双曲线函数关系 η=F(μ)[A₂(μ)+(B₂(μ))/(ε^1/2+C)],和ω=R_p/△R_p(△R_p指投影射程的标准偏差)比值的线性关系ω=A₃(μ)ε^1/21/2+B₃(μ),可简便而又准确地计算R,△R_p,R_p.这里F(μ),A₂(μ),B₂(μ), B₃(μ)和A₃(μ)为μ的代数函数,μ为离子与靶的质量比,C是经验常数.并对η等关系式的物理意义作了讨论。上述公式的计算结果与Gibbons的数值解结果及有关实验结果作了比较,表明可用于元素半导体如Si、二元化合物如GaAs以及三元化合物如SiO₂等;既对较轻离子适用,也对重离子适用,具有一定的普适范围。     

K+介子的三体轻子衰变

本文利用色散关系方法,假设普适V-A弱相互作用和奇异矢量流不守恒,从而对形状因子f₀,f₁的色散关系进行一次减去,计算了K_μ3⁺、K_e3⁺衰变中的π⁰能谱,K_μ3⁺衰变中的μ⁺能谱和μ⁺的纵向极化。计算中只考虑了K₁^*(m_*=888MeV)中间态对色散积分的贡献。参数σ取为+2.1的结果和实验在误差范围内相符合。放弃奇异矢量流部分守恒假设与实验符合的程度比保持这一假设要好一些。     

关于ι/η(1440)的结构分析

通过对J/ψ辐射衰变到K⁺K^－π⁰和K⁰_SK^±π⁺终态中iota能区的振幅分析,发现iota峰下有一个0^－+共振态(M=1467±3MeV,Γ=89±6MeV)和两个1⁺⁺共振态(M=1435±3MeV,Γ=59±5MeV; M=1497±2MeV,Γ=44±7MeV),分别对应于η(1440),f₁(1420)和f₁(1510).     

关于l/η(1440)的结构分析

本文通过对J/ψ辐射衰变到K⁺K^－π^O和K⁰_SK^±π⁺终态中iota能区的振幅分析,发现iota峰下有一个0^－+共振态(M=1467±3MeV,Γ=89±6MeV)和两个1⁺⁺共振态(M=1435±3MeV,Γ=59±5MeV;M=1497±2MeV,Γ=44±7MeV),分别对应于η(1440),f₁(1420)和f₁(1510).     

二元固溶体的配分函数

这篇论文是作者之一的某一篇论文的继续。论文分四节。在第一节中我们讨论的对象是应用二元混合气体的买厄理论至一个在AB型晶体上的二元固溶体而获得的不可约集团积分B(v₁,v₂)。我们严格地证明了它们是某一些晶体常数z₁,z₂,…的线性函数。这些常数的定义为1/((1/2)N)∑λ_abλ_a′b′…,式中N代表晶点阵的点的总数,λ_ab为邻矩阵,定义为λ_ab=1 如果ab为近邻, =0,如果ab不是近邻, a,a′,…互不相等,b,b′,…也互不相等,而乘积λ_ab…为全部下标的一个不可约乘积。证明共用了三个定理,同时也援用了一个所谓基本不可约集团的定义。在第二节中,我们应用了第一节的讨论对B(2,3)作了计算。在第三节中,我们应用第一节的结果,简化了求固溶体自由能的Kirkwood方法,同时也利用了简化的方法求得了自由能对(kT)^-1展开的幂级数中(kT)^-7的系数。比(kT)^-7更早的项的系数早已在作者之一的一篇论文中求得。在第四节中,我们利用第一节的结果,证明了严格理论在忽略z₂,z₃,…时即成了Bethe理论的第一级近似。如果将自由能表为z₁,z₂,…的函数而称它们的系数为f₁,f₂,…,那末我们指出:只消研究在某些赝点阵上的固溶体的配分函数,便可以求出f₁,f₂,…,同时我们也指出:在这些赝点阵上的固溶体的配分函数是可以(而也容易)严格地求出的,因此以上的理论供给了我们一个较好的求固液体的自由能的方法。     

Extended triplet set C343 of DNA sequences and its application to the p53 gene

Recently, much research has indicated that more and more cancers pose a threat to human life. Cancers are caused by oncogenes. Many human oncogenes have been found and most of them are located on chromosomes. The discovery of the oncogene plays a significant role in the treatment of cancer. The p53 tumor suppressor gene has received much attention because it frequently mutates or deletes in tumor cells of most people. Thus, the study of oncogenes is significant. In order to establish the Galois field (GF(7)), the indefinite gene is introduced as D and oncogene is introduced as O, and P. Taking the polynomial coefficients a₀, a₁, a₂ ∈ GF(7) and the bijective function f:GF(7) → {D,A,C,O,G,T,P}, where f(0) = D, f(1) = A, f(2) = C, f(3) = O, f(4) = G, f(5) = T, and f(6) = P, the bijective φ may be written as φ(a₀ + a₁x + a₂x²). Based on the algebraic structure, we can not only analyse the DNA sequence of oncogenes, but also predict possible new cancers.     

矢量介子φ的动力学模型及耦合常数fφKK2,fωKK2与fρKK2的值

假设矢量介子φ(Ι=0,ι=1,m_φ=7.30m_π)是K散射交换ρ,ω以及φ介子本身而形成的共振。应用双色散关系中的N/D方法,并设ρ,ω以及交换的φ介子的质量为已知,近似求出KK的分波散射振幅。当要求该振幅能重新给出正确的共振位置(φ的质量)和宽度时,即可得出偶合常数f_φKK²、f_ωKK²与f_ρKK²所必需满足的关系,从而给出它们可能取的数值。     

BSA-SDS-Ag聚合物纳米微粒的制备及其水凝胶性质的研究（Ⅰ）

报道了BSA－SDS－Ag聚合物纳米微粒的制备及水凝胶的性质,用X射线衍射（XRD）、透射电镜（TEM）、傅里叶变换红外（FT－IR）光谱考察了这种聚合物微粒的结构,微粒粒径32nm左右,用UV／Vis光谱及SEM考察了冰凝胶的性,表明Ag^ 离子先与BSA产生化学键合,再学原了Ag粒,进行聚合成网状结构的聚合物。     

Infrared Quantitative Study of Acetylation of Microspheres of Polystyrene

Abstract

Fourier transform infrared spectroscopy has been used to study quantitatively the acetylation of monodisperse polystyrene microspheres with diameters ranging from 7 to 9μm. The CH₂ stretching infrared vibration mode at 2921 cm^?1 was used as the internal intensity standard. The acetylation extent could be easily measured by comparing the relative intensities of the bands of acetyl group (1678, 1415, 1359 cm^?1) or the bands due to the para-substituted benzene ring to the band at 2921 cm^?1 from the calibration curve.     

Application of the method of X-ray fluorescence analysis for determination of the degree of chlorination of copper phthalocyanin

To whom correspondence should be addressd.     

混合物物态方程的计算

 在采用体积相加原理计算混合物物态方程的基础上,建立了一种物理模型确定混合物温度。根据混合物中各组分温度和压强平衡条件,采用压强-密度迭代方法计算给出混合物物态方程,编制了两种组分的混合物物态方程计算程序。为检验建立的温度模型的合理性及程序的有效性,分析了不同密度、温度状态的氢（H2）和钨（W）组成的混合物状态参量,计算了以下情形及其组合情形的混合物物态方程：H₂和W以不同质量比混合;质量比固定,单组分状态不同;温度区间和密度区间不同。研究表明:实际应用中在建立的混合物温度模型基础上确定的混合物物态方程是合理的。     

傅里叶望远镜外场实验性能改进和结果分析

为了实现对傅里叶望远镜成像系统更接近实际的仿真,改进了外场实验系统结构。采用反射式目标,利用准直扩束镜替代空间滤波器和准直透镜,使用大靶面电荷耦合器件作为监视器。在无大气和包含200m水平大气两种情况下,分别对2.5mm的4种不同空间频谱分布目标进行实验。实验选用9×9,17×17,33×33和65×65傅里叶分量分别进行重构。最高成像角分辨率为3.5″。结果表明含大气与无大气重构结果的Strehl比值相近,从而证明傅里叶望远镜成像系统能够克服下行链路低阶大气扰动的影响。     

Optical investigation of dynamics of phenomena of laser-based lithotripsy

Using time-resolved high-speed shadowgraphy, the dynamics of phenomena due to laser-based lithotripsy is studied. Collapsing mechanism of bubble formed therein is investigated. In order to study the mechanism, the optically implemented mathematical morphology is applied. The study of the shape of the plasma and the collapsing region of the bubble of fluid that we are studying can possibly be used for practical application for laser-based lithotripsy.     

Some peculiarities of deep PT-changes of physical properties of rocks

Abstract

Results of petrophysical PT-experiments are discussed. Used is a method of program modeling of experiments. Thermobaric dependence of elastic properties of acid, intermediate and basic rocks as well as elastic wave velocity anisotropy in amphibolites is studied. Deep PT-regimes effect on electrical resistance of dry and water-saturated rocks has been studied. PT-conditions of full loss of the remanent magnetization of volcanites have been established. A number of regional petrophysical lithosphere models has been constructed.     

分子费米共振拉曼光谱强度分析

测量了CCl₄和CS₂分子的Raman光谱。用Bertran理论和群论等相关理论对其光谱强度进行了分析,获得了发生费米共振分子的拉曼光谱强度的特殊规律： (1)发生费米共振的基频和倍频(和频)间发生能量转移,两光谱强度大小相互接近,当发生费米共振的基频和倍频(和频)间距离很小时,两发生费米共振的光谱强度相等(R=1);(2)能出现倍频光谱强度高于其基频光谱强度;(3)也会观测到费米共振光谱,而观测不到参与费米共振的和频中的基频光谱。此研究对化学、材料科学中的分子结构、材料成分等研究中的谱线认证、归属有很好的参考价值。     

Symmetry of Lagrangians of nonholonomic systems of non-Chetaev’s type

This paper studies the symmetry of Lagrangians of nonholonomic systems of non-Chetaev's type. First, the definition and the criterion of the symmetry of the system are given. Secondly, it obtains the condition under which there exists a conserved quantity and the form of the conserved quantity. Finally, an example is shown to illustrate the application of the result.     

Simulation of the contours of spectral lines of closed-ARC radiation

Simulated contours of self-reversed lines of Tl at 535 nm (7²S_1/2−6²P_3/2) and 378 nm (7²S_1/2-6²P_1/2) in alternating-current closed-arc radiation in mercury vapor with an addition of Tll were compared with experimental contours. It is shown that while a single self-reversed contour has many different sets of model parameters that ensure coincidence of experimental and calculated profiles, in the case of operation with a large data file of contours that correspond to different directions of observation along chords perpendicular to the discharge axis, and with different lines that have a common level, such a set of parameters becomes virtually unique. Instantaneous spatial distributions of Hg and Tl atoms in the ground state and of Tl atoms in the 6²P_3/2 state are determined and the parameters of the van der Waals broadening of the 7²S_1/2 level are found. It is shown that a considerable “red” shift of absorption contours in the outer layers of the discharge is observed. The results obtained contradict the presumed existence of local thermodynamic equilibrium in the given discharge. Reported at the Conference “Plasma Physics and Plasma Technologies,” Minsk, September 15–19, 1997 Petrozavodsk State University, 33, Lenin Ave, Petrozavodsk, 185640, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 761–768, September–October, 1998.