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Pair contact process with a particle source

Ronald Dickman·Wilson R. M. Rabelo·Geza Odor
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Abstract

We study the phase diagram and critical behavior of the one-dimensional pair contact process (PCP) with a particle source using cluster approximations and extensive simulations. The source creates isolated particles only, not pairs, and so couples not to the order parameter (the pair density) but to a non-ordering field, whose state influences the evolution of the order parameter. While the critical point p_c shows a singular dependence on the source intensity, the critical exponents appear to be unaffected by the presence of the source, except possibly for a small change in beta. In the course of our study we obtain high-precision values for the critical exponents of the standard PCP, confirming directed-percolation-like scaling.

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Ronald Dickman, Wilson R. M. Rabelo, Geza Odor. 2001-08-27. Pair contact process with a particle source. https://doi.org/10.1103/physreve.65.016118

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