VUV radiation impact on O(³P) atom surface loss on Pyrex in DC discharge in mixtures of O₂ with Ar, Kr and Xe

Abstract The effect of additives of Ar, Kr and Xe on the probability of О( 3 P) surface recombination, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mrow> <mml:msub> <mml:mi>γ</mml:mi> <mml:mi>o</mml:mi> </mml:msub> </mml:mrow> </mml:mrow> </mml:math> , on Pyrex in O 2 DC discharge has been studied in order to investigate the impact of vacuum ultraviolet (VUV) radiation on the atom loss. It is shown that within the measurement error, there is no effect of the sort of noble gas, as well as its amount on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mrow> <mml:msub> <mml:mi>γ</mml:mi> <mml:mi>o</mml:mi> </mml:msub> </mml:mrow> </mml:mrow> </mml:math> . The fluxes of VUV photons onto the tube surface under the considered conditions have been experimentally estimated. The phenomenological analysis of the results has revealed that the lifetime of reversible surface defects generated by VUV radiation should be small enough to have no effect on the kinetics of surface recombination of oxygen atoms. As estimated, this lifetime cannot exceed several seconds, which corresponds to the activation energy of the defect relaxation process of no more than ∼0.9 eV.