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1.
The extended x-rescaling model can explain the quark's nuclear effect very well. Weather it can also explain the gluon's nuclear effect should be investigated further. Associated J/ψ and γ production with large PT is a very clean channel to probe the gluon distribution in proton or nucleus. In this paper, using the extended x-rescaling model, the PT distribution of the nuclear effect factors of p+Fe→J/ψ+γ+X process is calculated and discussed. Comparing our theoretical results with the future experimental data, the extended x-rescaling model can be examined.  相似文献   
2.
The energy loss effect in nuclear matter is another nuclear effect apart from the nuclear effects on the parton distribution as in deep inelastic scattering process. The quark energy loss can be measured best by the nuclear dependence of the high energy nuclear Dre11-Yan process. By means of three kinds of quark energy loss parameterizations given in literature and the nuclear parton distribution extracted only with lepton-nucleus deep inelastic scattering experimental data, measured Dre11-Yan production cross sections are analyzed for 800 GeV proton incident on a variety of nuclear targets from FNAL E866. It is shown that our results with considering the energy loss effect are much different from those of the FNAL E866, who analyzes the experimental data with the nuclear parton distribution functions obtained by using the deep inelastic IA collisions and pA nuclear Drell-Yan data. Considering the existence of energy loss effect in Drell-Yan lepton pairs production, we suggest that the extraction of nuclear parton distribution functions shoul““““d not include Dre11-Yan experimental data.  相似文献   
3.
We present a study of associated ηc and γ double diffractive production in pp^- collision based on Ingelman-Schlein model, and the framework of non-relativistic QOD factorization formalism for quarkonia production. The prediction of ηc and γ is more reliable than J/ψ production, because the associated ηc and γ production is a pure color-octet process, and the dominant contribution comes from color octet ^1S0^(8) subprocess, which is related to the color octet matrix element of ^1S0(8) of J/ψ by the heavy quark spin symmetry and the large PT J/ψ production data. We find that the ratio of diffractive to inclusive cross sections is independent of the values of color octet matrix elements, but is sensitive to the gluon factor of the Pomeron and renormalized Pomeron flux factors. So experimental measurement of this ratio can give us more information of the nature of Pomeron and test the assumption of hard diffractive factorization in hadron-hadron collisions.  相似文献   
4.
The research work on the quantum effects in mesoscopic circuits has undergone a rapid development recently, however the whole quantum theory of the mesoscopic circuits should consider the discreteness of the electric charge. In this paper, based on the fundamental fact that the electric charge takes discrete values, the finite-difference Schrodinger equation of.the mesoscopic RLC circuit with a source is achieved. With a unitary transformation, the Schrodinger equation becomes the standard Mathieu equation, then the energy spectrum and the wave functions of the system are obtained. Using the WKBJ method, the average of currents and square of the current are calculated. The results show the existence of the current fluctuation, which causes noise in the circuits. This paper is an application of the whole quantum mesoscopic circuits theory to the fundamental circuits, and the results will shed light on the design of the miniation circuits, especially on the purpose of reducing quantum noise coherent controlling of the mesoscopic quantum states.  相似文献   
5.
The research work on the quantum effects in mesoscopic circuits has undergone a rapid development recently, however the whole quantum theory of the mesoscopic circuits should consider the discreteness of the electric charge. In this paper, based on the fundamental fact that the electric charge takes discrete values, the finite-difference Schrodinger equation of the mesoscopic RLC circuit with a source is achieved. With a unitary transformation, the Schrodinger equation becomes the standard Mathieu equation, then the energy spectrum and the wave functions of the system are obtained. Using the WKBJ method, the average of durrents and square of the current are calculated. The results show the existence of the current fluctuation, which causes noise in the circuits. This paper is an application of the whole quantum mesoscopic circuits theory to the fundamental circuits, and the results will shed light on the design of the miniation circuits, especially on the purpose of reducing quantum noise coherent controlling of the mesoscopic quantum states.  相似文献   
6.
The contribution of color-octet heavy quarkonium production mechanism in P Fe→J/ψ γ X process is calculated and discussed.The results show that color-octedt contributions are rather large and sometimes can exceed the color-singlet contributions,Using the structure function of Fe given by double Q2-rescaling model,the influence of nuclear effect on this process is also studied.  相似文献   
7.
Quantum Effects of Mesoscopic Inductance and Capacity Coupling Circuits   总被引:1,自引:0,他引:1  
Using the quantum theory for a mesoscopic circuit based on the discretenes of electric charges, the finite-difference Schrödinger equation of the non-dissipative mesoscopic inductance and capacity coupling circuit is achieved. The Coulomb blockade effect, which is caused by the discreteness of electric charges, is studied. Appropriately choose the components in the circuits, the finite-difference Schrödinger equation can be divided into two Mathieu equations in \hat p representation. With the WKBJ method, the currents quantum fluctuations in the ground states of the two circuits are calculated. The results show that the currents quantum zero-point fluctuations of the two circuits are exist and correlated.  相似文献   
8.
Starting from the point-view that the constituent quark has its own inner structure and according to the hypothesis of the maximum non-perturbative strong interaction reaction which should be obeyed in high energy strong-soft Processes ,we proposed a structure model of the Reggeon(R). In such processes a pair of constituent quark-antiquark in colliding hadrons would individually desociate with certain probahility into a non-perturbative gluon and a spinor-like cluster firstly. The spinor-like clusters will further emit non-perturbative gluons and then annihilate each other. Corresponding to such mechanism the relevant structure of R in the field theory can be represented by summing over a set of cutting ladder diagrams, where the vertical lines are the propagators of spinor-like clusters and the rungs are non-perturbative gluons. In the multi-Regge region where the energy of the system is very large and its momentum transfer│t│is very small, under the approximation that only the leading order logarithm terms of s are preserved, the scattering amplitudes for these cutting ladder diagrams are derived and summed. Thus, a compact formula of the typical Regge pole trajectory of mesons which are composed of light quarks is obtained.  相似文献   
9.
首先强调了在高能强作用软(高强软)过程,特别是在强子散射总截面中,单由Pomeron(IP)交换就渐进地饱和了幺正性条件这件事的重要性.结合对Landshoff和Nachtmann的IP场论模型适当修改,提出了最大非微扰强作用反应假说.与此相关,认为IP由这种反应中得出的一对共轭色八重态胶团组成.通过对修改后的q-q弹性振幅虚部图形的物理内涵的考察,一方面预言了高强软过程中会产生组分胶子,胶球态是由两个对撞的组分胶子熔合所形成.另一方面,通过这里的色胶团单圈图与Gell-mann-Zweig的介子散射时夸克图的对应,论证了IP与胶球态之间存在着Regge极点型的二元性关系.  相似文献   
10.
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