AUTOMATIC CALCULATION OF THE QUASISTATIONARY RATE OF THE METASTABLE STATE THERMAL DECAY
The thermal decay of a metastable state represents a wide range of physical and chemical processes. The examples of such process are the excited atomic nuclei fission, reaction of a diatomic molecular dissociation etc. The main characteristic of these processes is their rate (for example, the rate of dissociation: the portion of the molecules decaying per time unit with respect to the initial number of the molecules), namely its quasistationary value. The quasistationary rate of a metastable state thermal decay often might be calculated by means of the approximate analytical formulas (Kramers formulas). However, the results of such calculations possess inevitable errors caused by the approximations made during the derivation of the formulas. In order to calculate the quasistationary rate of a metastable state thermal decay more accurately, the numerical solution of the differential stochastic Langevin equations is usually applied. Using this solution one can construct the time-dependent decay rate which after some relaxation time achieves the constant within the fluctuations (quasistationary) value. In order to determine this quasistationary rate, every time it is necessary to decide which time interval should be taken for averaging. Such decision is usually made basing on empirical reasons. Within the present work, the developed by authors algorithm for automatic calculation the quasistationary decay rate is demonstrated. This algorithm allows to find the optimal time interval for averaging procedure and to minimize the error of the quasistationary rate.