共查询到20条相似文献,搜索用时 15 毫秒
1.
Tamás Csörgő 《Central European Journal of Physics》2004,2(4):556-565
A new family of simple analytic solutions of hydrodynamics is found for slowly expanding, rotationally symmetric fireballs
assuming an ideal gas equation of state. The temperature profile is position-independent only in the collisionless gas limit.
The Zimányi-Bondorf-Garpman solution and the Buda-Lund parameterization of expanding hydrodynamic particle sources are recovered
as special cases. The results are applied to predict new features of proton correlations and spectra for 1.93 AGeV Ni+Ni collisions. 相似文献
2.
M. D. Missarov 《Journal of statistical physics》1985,38(5-6):851-860
Wilson's renormalization group equations are introduced and investigated in the framework of perturbation theory with respect to the deviation of the renormalization exponent from its bifurcation value. We consider the case when the dimension is equal to 4. An exact solution of these equations is constructed using analytic renormalization of the projection Hamiltonians. 相似文献
3.
We consider a discretized volume V consisting of finite, congruent and attached copies of a tile t. We find a group L
V
the orbit of which, when applied to t, is just V. We show the connection between the structural matrixQ in the formal solution of a boundary value problem formulated for volume V and the so called auxiliary matrix of the graph Γ
v
associated with V. We show boundary value problems to be isomorphic if the graphs associated with the volumes are isomorphic, or, if the covering
groups are Sunada pairs. 相似文献
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Janos Polonyi 《Central European Journal of Physics》2003,1(1):1-71
These introductory notes are about functional renormalization group equations and some of their applications. It is emphasised
that the applicability of this method extends well beyond critical systems, it actually provides us a general purpose algorithm
to solve strongly coupled quantum field theories. The renormalization group equation of F. Wegner and A. Houghton is shown
to resum the loop-expansion. Another version, due to J. Polchinski, is obtained by the method of collective coordinates and
can be used for the resummation of the perturbation series. The genuinely non-perturbative evolution equation is obtained
by a manner reminiscent of the Schwinger-Dyson equations. Two variants of this scheme are presented where the scale which
determines the order of the successive elimination of the modes is extracted from external and internal spaces. The renormalization
of composite operators is discussed briefly as an alternative way to arrive at the renormalization group equation. The scaling
laws and fixed points are considered from local and global points of view. Instability induced renormalization and new scaling
laws are shown to occur in the symmetry broken phase of the scaler theory. The flattening of the effective potential of a
compact variable is demonstrated in case of the sine-Gordon model. Finally, a manifestly gauge invariant evolution equation
is given for QED. 相似文献
6.
B. M. Dzhagarov N. N. Kruk N. V. Konovalova A. A. Solodunov I. I. Stepuro 《Journal of Applied Spectroscopy》1995,62(2):285-289
Presented at the XV IUPAC Symposium on Photochemistry, Prague, July 17–22, 1994. 相似文献
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Bartolo Luque 《Central European Journal of Physics》2003,1(3):516-555
This work is a tutorial in Molecular Evolution from the point of view of Physics. We discuss Eigen's model, a link between
evolutionary theory and physics. We will begin by assuming the existence of (marco) molecules or replicators with the template
property, that is, the capacity to self-replicate. According to this assumption, information will be randomly generated and
destroyed by mutations in the code (i.e., errors in the copying process) and new bits of information will be fixed (made stable)
by the existence of an external pressure on the system (i.e., selection), and the ability of the molecules to replicate themselves.
Our aim is to build a model in order to describe molecular evolution from as general a standpoint as possible. As we will
see, even very simple models from the theoretical point of view will have surprisingly deep consequences. 相似文献
9.
Gely F. Zharkov 《Central European Journal of Physics》2005,3(1):77-103
Self-consistent solutions of the nonlinear Ginzburg-Landau (GL) equations are investigated numerically for a superconducting
(SC) cylinder, placed in an axial magnetic field, with a single vortex on the axis (m=1). Two modes, which show the original state of the cylinder, SC or normal (s
0 andn
0), are studied. The field increase (FI) and the field decrease (FD) regimes are studied. The critical fields destroying the
SC state withm=1 are found in both regimes. It is shown that in a cylinder of radiusR and GL-parameter ϰ, there exist a number of solutions depending only on the radial co-ordinater corresponding to different states such as M,e, d, p,i, n,
,n
*, and the state diagram on the plane of the variables (ϰ,R) is described. The critical fields corresponding to intrastate transitions and the onset of hysteresis are obtained. The
critical fieldH
0(R) dividing the paramagnetic and diamagnetic states of the cylinder withm=1 is determined. The limiting fields of supercooling or superheating of the normal state at which the restoration of the
SC state occurs are established. It is shown, that (in both casesm=1,0) there exist two critical parameters,
and
, which divide bulk SC into three groups (with
and
), in accordance with the behavior in a magnetic field. The parameters
and
mark the boundary for the existence of a supercooled normal
-state in FD-regime and a superheated SC M-state in FI-regime respectively. It is shown, that the value
, which was claimed in a number of papers as related to type-I superconductors, is illusory.
We regret to inform that Professor Gely Zharkov passed away on 9th July 2004. 相似文献
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本文考虑等离子体密度分布变化, 得到了修正屏蔽库仑势的解析解. 数值分析以及分子动力学模拟表明, 在常见实验室参数情况下, 等离子体密度分布变化引起的屏蔽库仑势修正对二维尘埃等离 子体系统的动力学和结构特性影响很小. 在极限参数情况下, 本模型的计算结果表明二维尘埃等离子体系统的扩散能力明显降低, 并且系统组态呈圆形分布. 此外, 本文还研究了实验室常见大小磁场对二维尘埃等离子体系统的影响.
关键词:
修正屏蔽库仑势
二维尘埃等离子体
分子动力学模拟 相似文献
12.
Saratov State University, 83 Astrakhanskaya Str., Saratov, 410601, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 62, No. 6, pp. 49–57, November–December, 1995. 相似文献
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采用密度泛函理论对H2与Rhn(n=1—8)团簇的相互作用进行了系统研究.结果表明, RhnH2体系的最低能量结构是在Rhn团簇最低能量结构的基础上吸附H原子生长而成.吸附H原子没有改变Rhn团簇的结构, 键长是影响Rhn和RhnH2磁矩的主要因素.从优化后的几何结构可以看出吸附后的H2发生断键,表明H2分子发生了解离性吸附.当n≤5,H原子的吸附以桥位为主,当n≥6时,H原子开始出现空位吸附.H原子的吸附提高了Rhn的稳定性和化学活性,较小的吸附能表明H原子易从RhnH2中解离出来.二阶能量差分表明4是RhnH2和Rhn团簇的幻数.
关键词:
nH2和Rhn团簇')" href="#">RhnH2和Rhn团簇
平衡结构
电子性质 相似文献
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Debajyoti Choudhury Rahul Sinha S Arunagiri Gautam Bhattacharyya Debrupa Chakraverty Debajyoti Choudhury Amitava Datta Anindya Datta Aseskrishna Datta Amol Dighe Dilip Kumar Ghosh Anjan Giri Stephen King Anirban Kundu Rukmani Mohanta Biswarup Mukhopadhyaya Sreerup Raychaudhuri Saurabh Rindani Probir Roy DP Roy Sourov Roy AI Sanda Nita Sinha Rahul Sinha K Sridhar H Yamamoto 《Pramana》2000,55(1-2):335-345
This report summarises the work done during WHEPP-6 (Institute of Mathematical Sciences, Chennai, India, Jan 3–15, 2000) in
Working group on ‘B and collider physics’. 相似文献
20.
The symmetry and |m| partial-wave analysis for two-dimensional (2D) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef
|m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (E<0) are just located at the poles off
|m|(θ) on the positive imaginaryk axis as is expected. In addition, as a function of |m|,f
|m|(θ) is analytically continuated to the complex |m| plane, the bound state energy eigenvalues are just located at the poles
off
|m|(θ) on the positive real |m| axis. 相似文献