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1.
利用BES上取得的9.0×106 J/ψ数据,进行了系统的J/物理分析.证实了ξ(2230)的存在,并首次发现ξ(2230)的非奇异衰变模式.测量了f0(980)、f2(1270)的共振参数和极化.对J/ψ→K+K-过程短分析的结果表明fJ(1710)是含有0++和2++两个态的宽结构.采用分波法测定了η(1440)、f0(1500)的自旋宇称,得到它们的主要衰变模式. 相似文献
2.
SIMULATION OF OCCUPATION FUNCTION FOR THERMALLY STIMULATED CONDUCTIVITY IN AMORPHOUS SEMICONDUCTORS
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The occupation functions for the general condition f(E,T), for the high field approx-imation (HTSC) fH(E,T) and for the steady state photoconductivity (SSPC) fP(E,T) in the thermally stimulated conductivity (TSC) of amorphous semiconductors have been inves-tigated. It was found that the occupation function f(E,T) in TSC is in excellent agreement with the occupation function in SSPC fP(E,T) under the condition of σTSC(T) = σP(T).There is a large difference between fP(E,T) and fH(E,T), which can be much reduced by introducing an effective attempt to escape frequency νeff in the calculation of fH (E, T). The results show that the mobility-lifetime product (μτ) in TSC obtained from SSPC measure-ments under the above condition is valid. For high field approximation TSC, the simulated νeff is found to be temperature dependent. 相似文献
3.
The implications of the f1(1285)-f1(1420) mixing for the K1(3P1)- K1(1P1) mixing angle are investigated. Based on the f1(1285)-f1(1420) mixing angle ∼ 50° suggested from the analysis for a substantial body of data concerning the f1(1420) and f1(1285), the masses of the K1(3P1) and K1(1P1) are determined to be ∼ 1307.35±0.63 MeV and 1370.03±9.69 MeV, respectively, which therefore suggests that the K1(3P1)- K1(1P1) mixing angle is about ±(59.55±2.81)°. Also, it is found that the mass of the h′1(1P1) (mostly of sˉ) state is about 1495.18±8.82 MeV. Comparison of the predicted results and the available experimental information of the
h1(1380) shows that without further confirmation on the h1(1380), the assignment of the h1(1380) as the sˉ member of the 1P1 meson nonet may be premature. 相似文献
4.
本文基于北京正负电子对撞机(BEPC)上北京谱仪(BES)所收集到的2.5×106J/ψ重建刻度后的事例,研究了强子衰变道J/ψ→ωf2(1270),f2(1270)→π+π-所揭示出的共振态f2(1270)的性质,测量了它的质量、宽度和分支比,利用最大似然法对角分布进行了拟合,给出自旋宇称为2++,首次得到螺旋度振幅比为x=0.99±0.29; y=-0.24±0.17; z1=0.90±0.57;z2=0.56±0.22. 相似文献
5.
讨论了强子衰变过程J/ψ→ωπ+π-包含的三个不同中间过程J/ψ→ωf2(1270),f2→π+π-和J/ψ→b1±(1235)π+,b1±→ωπ±的耦合问题.这种耦合效应的考虑对于精确测定共振态f2和b1±的参数以及这些反应道的螺旋度振幅比是十分重要的. 相似文献
6.
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. 相似文献
7.
通过对J/ψ辐射衰变到K+K-π0和K0SK±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). 相似文献
8.
用推广的矩分析方法讨论了过程J/ψ→X+f0(980),X→K+K-,f0(980)→π+π-.利用得到的矩表达式,可以确定玻色共振态X的自旋-宇称. 相似文献
9.
本文通过对J/ψ辐射衰变到K+K-πO和K0SK±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). 相似文献
10.
基于北京谱仪收集的7.0×106有中性触发的J/ψ事例,分析了J/ψ→γπ0π0衰变道.除了在π0π0不变质量谱中看到了众所周知的f2(1270)外,还证实了fJ(1710)和ξ(2230)的存在,同时给出了它们的质量以及相应的衰变分支比. 相似文献
11.
本文用推广的矩分析法研究了过程J/ψ→ωf2(1270),f2(1270)→ππ的极化结构,给出了用矩关系式表示的过程的四个螺旋度振幅之比. 相似文献
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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. 相似文献
14.
V.V. Anisovich A.V. Sarantsev 《The European Physical Journal A - Hadrons and Nuclei》2003,16(2):229-258
We present the results of the current analysis of the partial wave IJ
PC = 00+ + based on the available data for meson spectra ( ππ, KˉK,ηη,η,ππππ). In the framework of the K-matrix approach, the analytical amplitude has been reconstructed in the mass region 280 MeV < < 1900 MeV. The following scalar-isoscalar states are seen: comparatively narrow resonances f
0(980), f
0(1300), f
0(1500), f
0(1750) and the broad state f0(1200-1600). The positions of the amplitude poles (masses and total widths of the resonances) are determined as well as pole
residues (partial widths to meson channels ππ, KˉK,ηη,η,ππππ). The fitted amplitude gives us the positions of the K-matrix poles (bare states) and the values of bare-state couplings to meson channels thus allowing the quark-antiquark nonet
classification of bare states. On the basis of the obtained partial widths to the channels ππ, KˉK,ηη,η, we estimate the quark/gluonium content of f
0(980), f
0(1300), f
0(1500), f
0(1750), f0(1200-1600). For f
0(980), f
0(1300), f
0(1500) and f
0(1750), their partial widths testify the qˉq origin of these mesons though being unable to provide precise evaluation of the possible admixture of the gluonium component
in these resonances. The ratios of the decay coupling constants for the f0(1200-1600) support the idea about the gluonium nature of this broad state.
Received: 14 May 2002 / Accepted: 20 August 2002 / Published online: 11 February 2003
RID="a"
ID="a"e-mail: anisovic@thd.pnpi.spb.ru
Communicated by A. Sch?fer 相似文献
15.
本文在Thomas-Fermi势能基础上,导出了全射程R的解析解:R=2/a[E1/2-A1(arctg(2E1/2-f)/△1/2+arctg f/△1/2)+B1ln((E1/2-f)2)/(E-fE1/2+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/(Rp)(Rp指投影射程)比值的双曲线函数关系 η=F(μ)[A2(μ)+(B2(μ))/(ε1/2+C)],和ω=Rp/△Rp(△Rp指投影射程的标准偏差)比值的线性关系ω=A3(μ)ε1/21/2+B3(μ),可简便而又准确地计算R,△Rp,Rp.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。 相似文献
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本文基于北京正负电子对撞机(BEPC)上北京谱仪(BES)所收集到的国家自然科学基金资助.7.8×106J/ψ事例,系统研究了J/ψ→φπ+π-和J/ψ→ωπ+π-两个衰变道,给出了过程的分支比以及f0的位置和宽度参数,并对J/ψ→φf0,f0→π+π-过程的角分布进行了拟合,首次确定出该过程的螺旋度振幅比. 相似文献
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