  Dynamical hysteresis is a phenomenon which arises in ferromagnetic systems
below the critical temperature as a response to adiabatic variations of the
external magnetic field. We study the problem in the context of the mean-field
Ising model with Glauber dynamics, proving that for frequencies of the magnetic
field oscillations of order $N^{2/3}$, with $N$ the size of the system, the
"critical" hysteresis loop becomes random.
