Production and Backreaction of Fermions from Axion-$SU(2)$ Gauge Fields during Inflation

Understand

$SU(2)$ gauge fields and axions can have a stable, isotropic and homogeneous configuration during inflation.

• However, couplings to other matter species lead to particle production, which in turn induces backreaction on and destabilization of the non-abelian and axion background.
• In this paper, we first study the particle production by a $SU(2)$ gauge field coupled to a massive Dirac doublet.
• To carry out this calculation we have made two technical improvements compared to what has been done in the literature.