Hitting time and dimension in Axiom A systems and generic interval   excanges
  In this note we prove that for equilibrium states of axiom A systems the time $\tau_{B}(x)$ needed for a typical point $x$ to enter for the first time in a typical ball $B$ with radius $r$ scales as $\tau_{B}(x)\sim r^{d}$ where $d$ is the local dimension of the invariant measure at the center of the ball. A similar relation is proved for a full measure set of interval excanges. Some applications to Birkoff averages of unbounded (and not $L^{1}$) functions are shown. 
Stefano Galatolo