Decay of correlations for Fibonacci unimodal interval maps

We consider a class of generalized Fibonacci unimodal maps for which the central return times {s_n} satisfy that s_n=s_n-1 + κs_n-2 for some κ ≥ 1. We show that such a unimodal map admits a unique absolutely continuous invariant probability with exactly stretched exponential decay of correlations if its critical order lies in (1, κ + 1).