Eur. Phys. J. B 84, 137-145 (2011)
https://doi.org/10.1140/epjb/e2011-20288-5

Regular Article

Coherence resonances in excitable thermochemical systems induced by scaled reaction heat

¹ Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
² Physics Laboratory, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776, Warsaw, Poland
³ Institute of Chemistry, Jan Kochanowski University of Humanities and Sciences, Świętokrzyska 15G, 25-406 Kielce, Poland
⁴ Université Pierre et Marie Curie- Paris 6, Laboratoire de Physique Théorique de la Matière Condensée (LPTMC), 4 place Jussieu, case courrier 121, 75252 Paris Cedex 05, France
⁵ CNRS, LPTMC, UMR 7600, Paris, France

^a e-mail: bnowakowski@ichf.edu.pl

Received: 14 April 2011
Received in final form: 26 September 2011
Published online: 3 November 2011

Abstract

We study the influence of internal fluctuations on the dynamics of thermochemical systems which exhibit three distinct types of excitability. Simulations of the stochastic dynamics follow the master equation approach which describes appropriately the discrete changes of temperature due to a chemical reaction as well as continuous ones related to the exchange of energy with a thermostat. The relative deviations from the mean values of the interspike intervals are calculated as a measure of the coherence of the spike series. These variables exhibit minima as functions of scaled reaction heat for all the cases studied, proving the appearance of coherence resonance phenomena. Although reaction heat is not a usual parameter applied to control the level of fluctuations, the existence of coherence resonance can be explained as usual by the partition of the interspike interval into the escape and excursion times.