The production of molecules in a chemical reaction network is modelled as a
Poisson process with a Markov-modulated arrival rate and an exponential decay
rate. We analyze the distributional properties of M, the number of molecules,
under specific time-scaling; the background process is sped up by Nα,
the arrival rates are scaled by N, for N large. A functional central limit
theorem is derived for M, which after centering and scaling, converges to an
Ornstein-Uhlenbeck process. A dichotomy depending on α is observed. For
α≤1 the parameters of the limiting process contain the deviation
matrix associated with the background process.Comment: 4 figure