Study of striations in an AC glow discharge

Summary form only given, as follows. The striations that occur in a glow discharge is one of the best know, and yet not one of the best understood phenomena. They are widely reported in the literature as produced in DC discharges, and can be easily produced in AC discharges as well using the 60 Hz power supply line. In this case, the ionized gas becomes a nonlinear element in a periodically forced circuit, where the transition between different regimes of ordered and chaotic states can be studied. The striations themselves are manifestations of ionization oscillations and waves, where periodic changes in electron density are due to alternation of regions of predominant production and removal of electrons. In this work a cylindrical geometry discharge with plane electrodes at the ends are used, with filling pressures between 90 and 300 mtorr and voltages in the range of 520 and 1200 V for Ar. A description is made of the the main features of the AC discharges, as compared with those of DC ones.