J. Phys. IV France
Volume 08, Numéro PR6, October 1998
International Conference on Disorder and Chaos in honour of Giovanni Paladin
Page(s) Pr6-247 - Pr6-251
International Conference on Disorder and Chaos in honour of Giovanni Paladin

J. Phys. IV France 08 (1998) Pr6-247-Pr6-251

DOI: 10.1051/jp4:1998634

Numerical simulation of resonant activation in a fluctuating metastable model system

R.N. Mantegna and B. Spagnolo

Istituto Nazionale per la Fisica della Materia, Unità di Palermo and Dipartimento di Energetica ed Applicazioni di Fisica, Università di Palermo, viale delle Scienze, 90128 Palermo, Italy

We study the escape time from a metastable overdamped model system in the presence of two noise sources : a white noise and a random telegraph noise. The random telegraph noise controls the height of the potential barrier of the metastable system while the white noise mimics the presence of a given temperature. We report on numerical simulations about :
(i) the average residence time of the system in the metastable state ;
(ii) the probability density function (PDF) of the residence time at various values of the correlation time τc of the random telegraph noise. Resonant activation is observed in the dynamics of the investigated system. The PDF shows different shapes for different values of τc :
a) for very short values of τc and near the resonant activation regime a single exponential function ;
b) for very long values of τc the sum of two exponential functions ;
c) in the intermediate regime between a) and b) a shape which is well approximated by a stretched exponential function.

© EDP Sciences 1998