Ionization of air by radiation from a laser plasma

An ionization sensor with a time resolution of 50 ns was used to study the ionization of air by UV radiation from a laser plasma (produced by a pulsed TEA CO2 laser) at a distance of about 1 cm from the plasma boundary. It is shown that the behavior of the intensity of the ionizing radiation and the density of electrons produced by this radiation approximately repeats the form of the laser pulse. In addition, it is demonstrated that, owing to the multifrequency character of the ionizing radiation, there is observed a slow decrease in electron density with distance from the plasma boundary.