Microcanonical Monte Carlo Study of One Dimensional Self-Gravitating Lattice Gas Models

J. M. Maciel; M. A. Amato; T. M. Rocha Filho; A. D. Figueiredo

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arXiv · 1512.01391

Microcanonical Monte Carlo Study of One Dimensional Self-Gravitating Lattice Gas Models

J. M. Maciel·M. A. Amato·T. M. Rocha Filho·A. D. Figueiredo

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Abstract

In this study we present a Microcanonical Monte Carlo investigation of one dimensional self-gravitating toy models. We study the effect of hard-core potentials and compare to those results obtained with softening parameters and also the effect of the geometry of the models. In order to study the effect of the geometry and the borders in the system we introduce a model with the symmetry of motion in a line instead of a circle, which we denominate as $1/r$ model. The hard-core particle potential introduces the effect of the size of particles and, consequently, the effect of the density of the system that is redefined in terms of the packing fraction of the system. The latter plays a role similar to the softening parameter $ε$ in the softened particles' case. In the case of low packing fractions both models with hard-core particles show a behavior that keeps the intrinsic properties of the three dimensional gravitational systems such as negative heat capacity. For higher values of the packing fraction the ring the system behaves as the Hamiltonian Mean Field model and while for the $1/r$ it is similar to the one-dimensional systems.

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J. M. Maciel, M. A. Amato, T. M. Rocha Filho, A. D. Figueiredo. 2015-12-04. Microcanonical Monte Carlo Study of One Dimensional Self-Gravitating Lattice Gas Models. https://arxiv.org/abs/1512.01391

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