119407514
New solutions for charged anisotropic fluid spheres in general relativity
SummaryThe general analytical solutions for charged fluid distribution with anisotropic pressure are obtained. These solutions depend on an arbitrary generating function and the choice of an anisotropic function which measures the degree of anisotropy. As an illustration of the procedure some physically important examples are considered.
116059635
Viscous cosmological models with particle creation in Brans-Dicke theory
The effect of bulk viscosity on the evolution of the spatially flat Friedmann-Robertson-Walker models in the context of open thermodynamical systems, which allow particle creation, is analyzed within the framework of Brans-Dicke theory. Particle creation and bulk viscosity have been considered as separated irreversible processes. To accommodate the viscous pressure and creation pressure, which is associated with creation of matter out of gravitational field, the energy-momentum tensor is modified. Dynamical behaviour of the models have been discussed.
116888804
Bianchi type V and VI0 cosmological models in Lyra geometry
The Bianchi type V and VI0 models have been investigated in Lyra geometry in both the cases with the gauge function β is a time dependent and β=constant. The physical behaviour of these models has been discussed.
122637587
Bianchi type III and Kantowski-Sachs cosmological models in Lyra geometry
The cosmological models for Bianchi type III and Kantowski-Sachs space-time within the framework of Lyra geometry are obtained. The physical behaviour of the models have also been discussed.
119358995
A unified approach to charged-fluid distributions in general relativity
SummaryThe exact solutions for a charged perfect fluid are derived. The general analytical solution obtained depends on an arbitrary function of one of the space coordinates. As an illustration of the proposed method, the solution for a charged infinite plane has been obtained.
121611284
Some cosmological models with constant deceleration parameter
SummaryBerman (1983) presented a law of variation of Hubble’s parameter that yields constant deceleration parameter models of the Universe. In this paper, Robertson-Walker models have been studied in Einstein’s theory with cosmological term and in cosmological theory based on Lyra’s geometry. Some simple models have been obtained. The necessary relations in each model have been derived, considering a perfect fluid.
123842721
Multifractal study of singly charged particles produced in S-32 induced Ag/Br interactions at CERN
In this contribution, we describe an investigation of the fractal nature of non-statistical fluctuations in the density distribution of singly charged secondary particles produced in 32S-Ag/Br interactions in emulsion target at incident energy of 200A GeV. The experimental results have been compared with those obtained from an event sample simulated by the Lund Monte Carlo code FRITIOF. Besides obtaining the fractal dimensions and a smooth multifractal spectrum, show that the results can be used to determine universal parameters such as the Levy index, and the multifractal specific heat.
121441857
Centrality dependence of nonstatistical fluctuation in single particle density distribution in S-32-Ag/Br interaction at 200A-GeV/c
Nonstatistical fluctuations in the density distribution of shower tracks coming out of 32S–Ag/Br interaction at an incident momentum of 200A GeV/c, have been characterized by using the intermittency and multifractality techniques. A sample of 32S–Ag/Br nuclear emulsion events has been partitioned into three subsamples with respect to the shower track multiplicity in such a way that one can roughly estimate the average centrality for each subsample. Thereby, the centrality dependence of a set of relevant intermittency and multifractal issues has been investigated.
120052850
Search for entrance channel effects in heavy ion induced fusion reactions through the compound system79Rb
120176685
Intermittency and multiplicity moments of charged particles produced in 32S–Ag/Br interaction at 200 A GeV/c
The nature of nonstatistical fluctuations in the density distribution of singly charged particles produced in 32S–Ag/Br interactions at an incident momentum of 200 A GeV/c has been investigated. With the help of the nuclear photographic emulsion technique, the data were collected, and using different statistical methods of multiplicity moments these data have been analysed in terms of intermittency and fractal properties of one- and two-dimensional phase space distributions. Wherever possible, experimental results have been compared with the results obtained in other similar heavy-ion-induced experiments, as well as with those obtained from simulated events of the Lund Monte Carlo code FRITIOF. In some cases events simulated by generating (pseudo)random numbers have also been used for the purpose of comparison. The investigation shows the presence of weak intermittency in one dimension (1D) that is consistent with self-similarity in the density distribution. In two dimensions (2D), anisotropy in the distributions along longitudinal and transverse phase space variables indicates that self-affinity, rather than self-similarity in the distributions, is responsible for the observed behaviour. From the analysis of factorial correlators and oscillatory multiplicity moments, the presence of a few-particle short-range correlation has also been established. In almost all cases, the simulated interactions fail to replicate the experimental results.
122194176
Search for entrance channel effects in heavy ion induced fusion reactions via neutron evaporation