期刊：
EUROPEAN PHYSICAL JOURNAL C,1995年68(3):463-465 ISSN：1434-6044
通讯作者：
ZHANG, Y
作者机构：
[ZHANG, Y; LIU, LS] Institute of Particle Physics, Hua-Zhong Normal University, Wuhan, China
通讯机构：
[ZHANG, Y] H;HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
关键词：
Field Theory;Density Function;Elementary Particle;Monte Carlo Simulation;Quantum Field Theory
摘要：
It is shown through theoretical analysis and Monte Carlo simulation that when the translational invariance of semi-inclusive density function is destroyed the bin-wise and strip integrals of this function are inequivalent. The different experimental results about the anomalous scaling behaviour of factorial moment in the variables (y, p perpendicular to, phi) and that of strip integral in the variable Q(2) is discussed briefly.
通讯机构：
[HOU, DF] H;HUAZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
关键词：
有效势;自洽计算;Higgs模型;重子对称性
摘要：
By developing the ''tadpole graph method'' including the resummation of the hard thermal loops in the tadpole diagrams, a self-consistent method is proposed in the calculation of effective potential. It is shown that the calculated effective potential at finite temperature in the Higgs model is more self-consistent than the naive calculation. The two difficulties encountered in the naive calculations of the effective potential disappear naturally, The calculated results indicate that the symmetry restoration transition is of the first order.
摘要：
Charged particle pseudorapidity density distributions in Au induced reactions in nuclear emulsion at 10.7 A GeV have been measured. In peripheral events the shower particle distribution exhibits a two peak structure while in central collisions it has a Gaussian shape. The spectator protons appear in the second peak in the pseudorapidity spectra and exhibits a broader momentum distribution than expected from Fermi motion. The produced particle yield in central collisions is not substantially different from phenomenological descriptions based on data from O and S induced reactions.
作者机构：
FREE UNIV BERLIN,INST THEORET PHYS,D-14195 BERLIN,GERMANY.;HUAZHONG UNIV SCI & TECHNOL,DEPT PHYS,WUHAN 430074,PEOPLES R CHINA.;[YANG, CB] HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
通讯机构：
[YANG, CB] H;HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
摘要：
The ratio K/pi in pp collisions is investigated based on the constraints of the isospin conservation and the strangeness suppression. Numerical results on the ratios of K+/pi(+) and K-/pi(-) are given for the relationship between the ratio and the multiplicity of produced particles.
作者机构：
CHINA CTR ADV SCI & TECHNOL,WORLD LAB,BEIJING 100080,PEOPLES R CHINA.;HUAZHONG UNIV SCI & TECHNOL,NATL LAB LASER TECHNOL,WUHAN 430070,PEOPLES R CHINA.;[YA, J] HUAZHONG NORMAL UNIV,DEPT PHYS,WUHAN 430070,PEOPLES R CHINA.
通讯机构：
[YA, J] H;HUAZHONG NORMAL UNIV,DEPT PHYS,WUHAN 430070,PEOPLES R CHINA.
摘要：
The transient properties of a single-mode dye laser with correlations between additive and multiplicative white-noise terms are investigated theoretically. The mean, variance, and skewness of first-passage-time distributions for the white-noise-loss model and the white-noise-gain model are obtained. We find that (1) the mean first-passage time for the two models is not affected by the strength λ of the correlation between additive and multiplicative noise terms; (2) as λ is increased, the magnitudes of the variance and skewness of the two models are increased; and (3) under the same λ and the same pump level, the variance and skewness of the white-noise-gain model are larger than those of the white-noise-loss model.
摘要：
By means of adiabatically eliminating the upper level or levels of a Λ-configuration atom coupling to a two-mode quantized field, we have studied the influences of ac Stark shifts on the atomic coherent population trapping in two important atom-field coupling systems via nondegenerate Raman two-photon processes. The states of the field that trap the atom in its two nondegenerate lower levels are obtained, and the important roles of ac Stark shifts and properties of the atomic upper level or levels in the states of the trapping field in two Raman-coupling systems are also analyzed.
期刊：
EUROPEAN PHYSICAL JOURNAL C,1995年66(3):473-484 ISSN：1434-6044
通讯作者：
CAI, X
作者机构：
LUND UNIV,DIV COSM & SUBATOM PHYS,S-22362 LUND,SWEDEN.;CHINA UNIV GEOSCI,DEPT APPL GEOPHYS,WUHAN 430074,PEOPLES R CHINA.;[CAI, X] HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
通讯机构：
[CAI, X] H;HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
关键词：
Field Theory;Phase Space;Elementary Particle;Quantum Field Theory;Limited Size
摘要：
A possible universal description of rapidity dependence of multiplicity distributions in high energy e(+)e(-), mu p, hh, hA and AA collisions is proposed based on a cluster mechanism, local charged compensation and its violation. It appears that there exist a statistical connection between multiplicity distribution in a full longitudinal phase space and that in a selected rapidity window with limited size.
作者机构：
ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING,PEOPLES R CHINA.;PANJAB UNIV,DEPT PHYS,CHANDIGARH 160014,INDIA.;HUNAN EDUC INST,DEPT PHYS,CHANGSHA,PEOPLES R CHINA.;JOINT INST NUCL RES,HIGH ENERGIES LAB,DUBNA,RUSSIA.;UNIV RAJASTHAN,DEPT PHYS,JAIPUR 302004,RAJASTHAN,INDIA.
通讯机构：
[ADAMOVICH, MI] K;KAZAKH ACAD SCI,INST HIGH ENERGY PHYS,ALMA ATA,KAZAKHSTAN.
摘要：
Pseudorapidity density and multiplicity distributions of charged particles produced in heavy-ion collisions at the BNL AGS have been studied. The multiplicity distributions and pseudorapidity distributions of shower particles in Au-induced interactions are presented and compared with model predictions from RQMD, FRITIOF and VENUS. It is shown that the widths of the pseudorapidity distributions of produced particles in central collisions are independent of the interacting system. The results from EMU01 have been compared, and found to agree, with the results from two other heavy-ion experiments, E802 and E814.
期刊：
EUROPEAN PHYSICAL JOURNAL A,1995年351(3):311-316 ISSN：1434-6001
通讯作者：
ADAMOVICH, MI
作者机构：
ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING,PEOPLES R CHINA.;PUNJABI UNIV,DEPT PHYS,CHANDIGARH 160014,INDIA.;HUNAN EDUC INST,DEPT PHYS,CHANGSHA,PEOPLES R CHINA.;JOINT INST NUCL RES,HIGH ENERGIES LAB,DUBNA,RUSSIA.;UNIV RAJASTHAN,DEPT PHYS,JAIPUR 302004,RAJASTHAN,INDIA.
通讯机构：
[ADAMOVICH, MI] I;INST HIGH ENERGY PHYS,ALMATY,KAZAKHSTAN.
摘要：
The fragmentation topology of Si-28 at 3.7 A GeV and 14.6A GeV and S-32 at 200A GeV in reactions with emulsion nuclei is presented. The fragmentation cross sections are very similar at all three energies. A statistical percolation model can qualitatively describe the data for Z greater than or equal to 6. The He production is underestimated and the 3 less than or equal to Z less than or equal to 5 fragments overestimated by this model.
摘要：
By analyzing the fourth-order dispersion relation, the influence of coupled radial and azimuthal perturbations on the stability of a radiation-pressure-dominated accretion disk is investigated. If the azimuthal perturbations are considered, we find that the stability properties of disk are different from that in purely radial perturbation case. For a standard α disk model, the thermal instability is the dominant instability, and it is enhanced in the presence of azimuthal perturbations, while the viscous mode and the acoustic modes tend to become stable with the increase of azimuthal perturbation wavenumber. The increase of viscosity will enhance the instabilities of thermal and viscous modes, as well as that of acoustic modes. The acoustic instability exists only in the case without azimuthal perturbations or with very low azimuthal wavenumber. For a slim disk model, the situation is quite similar except that the thermal and viscous modes are never unstable in the absence of azimuthal perturbations, where the acoustic instability is dominant.
作者机构：
INST HIGH ENERGY PHYS,ALMA ATA,KAZAKHSTAN.;ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING,PEOPLES R CHINA.;INST GRAVITAT & SPACE RES,BUCHAREST,ROMANIA.;PANJAB UNIV,DEPT PHYS,CHANDIGARH 160014,INDIA.;HUNAN EDUC INST,DEPT PHYS,CHANGSHA,PEOPLES R CHINA.
通讯机构：
[HOU, DF] H;HUAZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
关键词：
Weinberg-Salam模型;顶夸克;弱电相移;重子对称性
摘要：
The effective potential of the Weinberg-Salam (WS) model is calculated at finite temperature and in the chemical potential of top quarks according to the grand canonical ensemble temperature field theory. The electroweak transition is studied at hot and density conditions. It is indicated that the symmetry restoring transition can take place either by increasing the temperature or chemical potential of top quarks, but at high temperature and in the low chemical potential the transition is of the first order, and it becomes the second order at a cold density condition. The phase diagrams are showed.
摘要：
A radial-azimuthal stability analysis of a geometrically thin, gas-pressure-dominated accretion disk is presented. In the purely radial perturbation case, the disk is pulsationally unstable to the acoustic modes but stable to the thermal and viscous modes. If the coupling of radial and azimuthal perturbations is considered, the stability properties of the disk are different. With the increase of azimuthal wavenumber, the acoustic modes tend to become stable while the viscous mode becomes unstable. The acoustic instability exists only for large viscosity and small azimuthal wavenumber, while the viscous instability exists for small viscosity and large azimuthal wavenumber. The inclusion of azimuthal perturbations, however, has nearly no effect on the stability of thermal mode, which is always stable in the disk. The influence of opacity on the stability of a gas-pressure-dominated disk has also been investigated. We find that if the free-free absorption dominates the opacity, the disk is more stable than that with electron-scattering domination.
摘要：
On the basis of the nontopological soliton bag model, it is proposed that the quark decon-finement may be indicated by the unstability and disappearance of solition solutions at finite-temperature and finite-density. The thermal effects on the vacuum structure of strongly interacting matter are investigated, and the soliton field equation of the model is solved directly in the whole range of temperature via a numerical method. The phase structure of the system and the features of deconfining phase transition are analysed in detail. In addition, the collective excitations in the vacuum caused by thermal effects are investigated by making use of an order parameter which is given to describe the vacuum condensation at finite temperature. A physical mechanism and an intuitive picture are presented for the formation of QGP from both deconfined hardon matter and the vacuum excitation in relativistic heavy ion collisions.
摘要：
The anomalous scaling of factorial moments with continuously diminishing scale is studied using a random cascading model. It is shown that the model currently used have the property of anomalous scaling only for descrete values of elementary cell size. A revised model is proposed which can give good scaling property also for continuously varying scale. It turns out that the strip integral has good scaling property provided the integral regions are chosen correctly, and that this property is insensitive to the concrete way of self-similar subdivision of phase space in the models.
作者机构：
[WU, YF; ZHANG, Y; LIU, LS] Institute of Particle Physics, Hua-Zhong Normal University, Wuhan 430070, China
通讯机构：
[WU, YF] H;HUA ZHONG NORMAL UNIV,INST PARTICLE PHYS,WUHAN 430070,PEOPLES R CHINA.
摘要：
The experimental results on factorial moments (FM’s) in different phase space dimensions are examined in some detail. The general trends of one- and three-dimensional FM’s and the complexity of the two-dimensional ones are pointed out. It is shown that all the complicated patterns of FM’s in different dimensions can be understood comprehensively under the assumption of self-affine fluctuations in 3D, which means that anomalous scaling of FM’s may exist in multiparticle final states provided the shrinkage of phase space is done correctly according to the anisotropic property of multiplicity fluctuations.
期刊：
Astrophysics and Space Science,1995年232(2):293-306 ISSN：0004-640X
通讯作者：
Yang, LT
作者机构：
ACAD SINICA,BEIJING ASTRON OBSERV,BEIJING 100080,PEOPLES R CHINA.;GEZHOUBA INST WATER ELECT POWER,DEPT FUNDAMENTAL SCI,YICHANG,PEOPLES R CHINA.;[Yang, LT] HUAZHONG NORMAL UNIV,INST ASTROPHYS,WUHAN 430070,PEOPLES R CHINA.
通讯机构：
[Yang, LT] H;HUAZHONG NORMAL UNIV,INST ASTROPHYS,WUHAN 430070,PEOPLES R CHINA.
关键词：
Viscosity;Magnetic Field;Time Variation;Mach Number;Accretion Disk
摘要：
The electronic structures of small sulfur clusters, S2– S12, are calculated using the ab initio self-consistent discrete variational local-density-functional method, and the calculated ionization potential curve is in good agreement with that from experiment in the range from S2 to S8, and the calculated ionization potentials of clusters from S9 to S12 are reliably predicted where measurements are lacking. We suggest that the different mixtures of atomic orbitals 3s and 3p on the highest occupied molecular orbitals for different clusters are related to the change of ionization potential with the cluster size. In addition, we point out that the two sulfur dimers in S4 are bound by the van der Waals force.
