Laser Diagnostics of High Vibrational and Rotational H2-States

Abstract

We report on measurements of vibrational and rotational excited electronic-ground-state hydrogen molecules in a magnetic multipole plasma source by LIF with VUV radiation. The measurements are taken after rapid shut-off of the discharge current. Absolute level populations are obtained using Rayleigh scattering calibration with Krypton. The theoretically predicted suprathermal population of the vibrational distribution is clearly identi.ed. We found also non-Boltzmann rotational distributions for the high vibrational states. The addition of noble gases (Argon and Xenon) to hydrogen leads to a decrease of the vibrational population.