Power suppressed corrections to hadronic event shapes

For high energy processes (M ⪢ ΛQCD) there are infrared safe hadronic shape variables that have a calculable perturbative expansion in αs(M2). However, nonperturbative power suppressed corrections to these variables are not well understood. We use the behavior of large orders of the perturbation expansion to gain insight into the nonperturbative corrections. Our results suggest that certain shape variables have nonperturbative corrections suppressed by fractional powers of ΛQCD2M2.