Supertransient magnetohydrodynamic turbulence in Keplerian shear flows.

A subcritical transition to turbulence in magnetized Keplerian shear flows is investigated by using a statistical approach. Three-dimensional numerical simulations of the shearing box equations with zero net magnetic flux are employed to determine the transition from decaying to sustained turbulence as a function of the magnetic Reynolds number R{m}. The results reveal no clear transition to sustained turbulence as the average lifetime of the transients grows as an exponential function of R{m}, in accordance with a type-II supertransient law.