Quintessential inflation in Palatini gravity

We study a model of quintessential inflation in the context Palatini gravity. As representative example, we consider Peebles-Vilenkin with small non-minimal coupling to gravity, which is consistent most recent Planck measurements. At end inflation, inflaton field passes through tachyonic region and it leads explosive particle production preheating process. After preheating, Universe becomes dominated by kinetic energy enters period kination. Eventually, total density radiation, resulting reheating. find that predicts reheating temperature values $T_{\rm{RH}} \sim \mathcal{O}(10^3 - 10^8) \, \rm{GeV}$, significantly above Big Bang Nucleosynthesis. Following reheating, rolls down quintessence potential until freezes. Since remains frozen present day, residual at this value explains observed dark density.