Fundamentals and application of an expanding hydrogen low-pressure plasma jet

The absolute density of atomic hydrogen excited states in two different regimes of a magnetized expanding plasma is determined using emission and absorption spectroscopy. First evidence has been found for the presence of high densities of negative ions in the "atomic" (recombining) regime of an expanding hydrogen plasma. Several clear observations of the presence of "hot" electrons have been made in the "molecular" (ionizing) regime of the expanding plasma. For both regimes the absolute density of atomic hydrogen in the ground state and the degree of plasma dissociation have been determined