QCD axions and axionlike particles in a two-inflation scenario
  We investigate the phenomenology of QCD axions and axionlike particles in a
scenario with two eras of inflation. In particular, we describe the possible
solutions for the QCD axion field equation after the second inflation and
reheating. We calculate the dilution numerically for QCD axions and give an
analytic approximation for axionlike particles. While it has been realised
before that such a scenario can dilute the axion energy density and open up the
parameter space for the axion decay constant $f_A$, we find that even a small
increase in the relative QCD axion energy density is possible.
