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1.
We study the mixing of pseudo-Goldstone bosons predicted by technicolor theory and the effects on HERA high-Q2 events. We find that: (a) there eyist two F = 0 scalar leptoquarks P3′ with m(P3′) = 200 GeV and P30 with m(30) =225 GeV for β1 = β2 = 0.4; (b) the P3′ and P30 can contribute the required cross section to account for the excesses of NC and CC high-Q2 events; (c) the coexistence of P3′ and P30 may be responsible for the splitting of averaged mass of the H1 and ZEUS high-Q2 neutral current events.  相似文献   

2.
A. Mehta 《Pramana》2003,61(5):819-826
In this paper recent measurements of structure functions from the HERA Collaborations are presented.  相似文献   

3.
At lowx, an analytic solution of the DGLAP equation for gluon in the next-to-leading order (NLO) is obtained by applying the method of characteristics. Its compatibility with double leading logarithmic approximation (DLLA) asymptotics is discussed and comparison with the exact ones like GRV98NLO is made. The solution is then utilized to calculate the derivatives∂F 2 (x,Q 2)/ lnQ 2 and ∂ lnF 2(x,Q 2)/ ln (1/x) and compared with the recent HERA data. Our solution is found to reproduce most of the essential features of the data on the derivatives.  相似文献   

4.
5.
讨论计算了TC2模型预言的Top介子在HERA和构想中的THERA对撞机上对t道eq→et过程中的单顶夸克产生的贡献.结果表明:中性Top介子对ec→et过程中的单顶夸克产生有较大的贡献.在绝大部分参数空间内,过程的产生截面在1—6pb范围内,因此,在HERA和THERA对撞机上通过eq→et过程可探测中性Top介子的可能物理迹象  相似文献   

6.
We estimate the cpntributions to HERA e±p deep inelastic scattering process from the color-triplet pseudo-Goldstone bosons appeared in technicolor theory. We find that the F = 0 scalar technicolor leptoquark P3', the lighter mixed state of charge 2/3 color-triplet pseudo-Goldstone bosons, can provide the required extra contributions to account for the excesses of both neutral and charged current events with very high Q2 at HERA simultaneously.  相似文献   

7.
魏群 《物理学报》2009,58(5):3485-3490
采用完全对角化方法,以尖晶石结构的ZnAl24:Cr3+,ZnGa24:Cr3+和MgAl24:Cr3+系列晶体为例,联系晶格局域结构,对三角对称下3d3离子2Eg因子性质进行了研究.研究中考虑了包括自旋与自旋相互作用、自旋与另一轨 关键词: 2Eg因子')" href="#">2Eg因子 3离子')" href="#">3d3离子 尖晶石结构 磁相互作用  相似文献   

8.
 在高温高压下合成出了单相的Ba2CuO2Cl2化合物,在高压下对该化合物晶体结构的稳定性进行了研究。结果表明,在实验测量的压力范围内,Ba2CuO2Cl2化合物的晶体结构是稳定的,并且其压缩性表现出较强的各向异性,计算得到了Ba2CuO2Cl2化合物的体弹模量和状态方程。  相似文献   

9.
Contraposing the characteristics of PHY in optical LAN, an on-line method for Q factor detection basing on DSP technology is put forward and its mathematical physical prototype is discussed. A series of simulative tests indicates that the method is valid, feasible, and convenient.  相似文献   

10.
Hyperfine interactions of Na isotopes in single crystals have been studied using highly nuclear polarized 20,21,26,27,28Na beams provided by ISAC/TRIUMF. The degree of polarization kept in the crystals, the spin-lattice relaxation times, the electric quadrupole coupling constants and the initial distribution of the populations were measured. Such knowledge is indispensable for the application of the hyperfine interactions in the study of precision measurements such as the nuclear structure through nuclear moments and the fundamental symmetries.  相似文献   

11.
高永华  何祯民  段春贵 《物理学报》2001,50(6):1028-1034
提出了改进的双重Q2重标度模型,在保持核动量守恒的条件下,用唯象的方法找到了一套重标度参数公式,建立了重标度参数ξvs及ξg与原子核平均结合能之间的联系.利用该模型所得到的束缚核子内部分子分布函数,对核DIS过程,核Drell-Yan过程和J/Ψ光生过程均给出满意的解释 关键词: 2重标度模型')" href="#">双重Q2重标度模型 核效应 结合能  相似文献   

12.
We report here about measurements of reaction and decay Q values by precise determination of pairs of atomic masses. These were performed with the Penning trap mass spectrometer SMILETRAP. Measurements with Penning traps give reliable and accurate masses, in particular Q values, due to the fact that certain systematic errors to a great deal cancel in the mass difference between the two atoms defining the Q value. Some Q values that are of fundamental interest will be discussed here, for example, a new Q value for the 6Li (n,γ) 7Li reaction, for the β-decay of tritium, related to properties of the electron neutrino mass, and for the neutrino-less double β-decay of 76Ge, related to the question of whether the neutrino is a Majorana particle or not. In case of the latter two we report the most accurate Q values, namely 18,589.8(12) eV for the tritium decay and 2,038.997(46) keV for the neutrino-less double β-decay of 76Ge.  相似文献   

13.
14.
Levofloxacin (LEV) is a fluoroquinolone antimicrobial agent. LEV also inhibits DNA synthesis and is bactericidal. The mechanisms of the interaction among LEV, DNA and Cu2+ are studied by fluorescence method. In the paper, the results show that LEV and Cu2+ can form binary complex, and also LEV and DNA can form complex mediated by Cu2+. The composition of the complex is determined. The affects to the reaction are also found.  相似文献   

15.
Experiences obtained from recent improvements in the performance of solid-state (14)N MAS NMR spectroscopy have been used in a natural abundance (33)S MAS NMR investigation of the satellite transitions for this interesting spin I=3/2 isotope. This study reports the first observation of manifolds of spinning sidebands for these transitions in (33)S MAS NMR as observed for the two alums XAl(SO(4))(2) x 12H(2)O with X=NH(4) and K. For the NH(4)-alum a variable temperature (33)S MAS NMR study, employing the satellite transitions, shows that the (33)S quadrupole coupling constant (C(Q)) exhibits a linear temperature dependence (in the range -35 degrees C to 70 degrees C) with a temperature gradient of 3.1 kHz/ degrees C and undergoes a sign change with zero-crossing for C(Q) at 4 degrees C (277 K). For the isostructural K-alum a quite similar increase in the magnitude of C(Q) with increasing temperature is observed, and with a temperature gradient of 2.3 kHz/ degrees C. Finally, for optimization purposes, a study on the effect of the applied pulse widths at constant rf field strength on the intensity and variation in second-order quadrupolar lineshape for the central (1/2<-->-1/2) transition of the K-alum has been performed.  相似文献   

16.
The electric quadrupole coupling constants eqQ/h of 8B (, T 1/2 = 769 ms) and 13B (, T 1/2 = 17.4 ms) in single crystal TiO2 have been precisely measured by the β-NQR technique. The ratios of these Q moments to Q(12B) were determined as ∣Q(8B)/Q(12B)∣ = 4.882(32) and ∣Q(13B)/Q(12B)∣ = 2.768(24).  相似文献   

17.
We study the L p -spectrum of the Laplace–Beltrami operator on certain complete locally symmetric spaces with finite volume and arithmetic fundamental group Γ whose universal covering X is a symmetric space of non-compact type. We also show, how the obtained results for locally symmetric spaces can be generalized to manifolds with cusps of rank one.   相似文献   

18.
The momentum dependences of the nuclear spin polarization P and alignment A of 13B(, T 1/2 = 17.36 ms) produced in the 100A MeV 15N + Be collisions have been measured by detecting β-ray asymmetry. Because both the P and A were significantly smaller than the prediction from a simple kinematical model, some relaxation mechanisms must be take into account. Comparing the signs of the observed alignment of 12B, the sign of the quadrupole coupling constant eqQ of 13B in TiO2 was determined to be positive.  相似文献   

19.
We study the diagonalization problem of certain discrete quantum integrable models by the method of Baxter's TQ relation from the algebraic geometry aspect. Among those the Hofstadter type model (with the rational magnetic flux), discrete quantum pendulum and discrete sine-Gordon model are our main concern in this report. By the quantum inverse scattering method, the Baxter's TQ relation is formulated on the associated spectral curve, a high genus Riemann surface in general, arisen from the study of spectrum problem of the system. In the case of degenerated spectral curve where the spectral variables lie on rational curves, we obtain the complete and explicit solution of the TQ polynomial equation associated to the model, and the intimate relation between the Baxter's TQ relation and algebraic Bethe Ansatz is clearly revealed. The algebraic geometry of a general spectral curve attached to the model and certain qualitative properties of solutions of the Baxter's TQ relation are discussed incorporating the physical consideration.  相似文献   

20.
Excited states of 63Cu were populated via the 52Cr+10O (65 MeV) reaction using the gamma detector array equipped with charged particle detector array for reaction channel separation. On the basis of γ-γ coincidence relations and angular distribution ratios, a level scheme was constructed up to E n=7 MeV and J π=23/2(+). The decay scheme deduced was interpreted in terms of shell model calculations, with a restricted basis of the f 5/2, p 3/2, p 1/2, g 9/2 orbitals outside a 56 28Ni core.  相似文献   

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