Non-perturbative Corrections to Particle Production from Coherent Oscillation

Understand

We investigate particle production from coherent oscillation by using the method based on the Bogolyubov transformation.

• Especially, we study the case when the amplitude of the oscillation and also the coupling constants with the oscillating field are small in order to avoid the non-perturbative corrections from the broad parametric resonance.
• We derive the expressions for the distribution functions and the number densities of produced particles at the leading order of coupling constant.
• It is, however, found that these results fail to describe the exact particle production eventually due to the non-perturbative effects even if the coupling constants are small.