Xe gas in low pressure discharge tubes (20 mm diameter, 800 mm length, commercial hollow electrodes at 650 mm distance, 50 Hz, 60 mA) was quantitatively determined using quadrupole mass spectrometry (QMS). The temporal Xe gas evolution over 5 to 20 h of gas discharge revealed the consumption and recovery of Xe gas to be dependent on the prevailing gas composition. The net consumption in the standard Xe/He(2.0/98) gas mixture was much faster than that in Xe/Kr/He(1.9/93/5). Xe recovery during discharges in ‘preloaded’ tubes refilled with pure gas revealed an increasing efficiency in the sequence He < Ne < Ar < Kr, being most efficient with the first refilling. The temporal evolution of Xe gas was simulated by a kinetic model based on two equilibria between Xe gas and Xe incorporated in the glass tube walls (1) and the electrodes (2). It is concluded that the experimental setup, the elaborated measurement procedures and the kinetic model provide a good basis for further quantitative investigations. The net Xe gas consumption during discharge, which is presently limiting the tube lifetime, may be reduced particularly by improving the discharge gas composition and the electrode materials.

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Thin polycrystalline ZnSe:Mn films made by vacuum deposition on amorphous glass substrates are annealed by the scanned beam of a high‐power argon cw laser operated at the 457.9 nm wavelength. Melting and degradation of the films is observed if the laser intensity exceeded distinct threshold values which were characteristic for each of the both processes. The thresholds are determined by a new method which takes advantage of the Gaussian intensity profile of the laser beam and may be generally applied for systems of an absorbing thin film on a nonabsorbing substrate with low thermal conductivity. Cathodoluminescence measurements indicate that the luminescence properties of the ZnSe:Mn films can be improved by cw laser annealing with intensities ranging between the melting and the degradation threshold.