The radiative efficiency of the 147 nm resonance radiation of Xe excited in a low pressure, high-frequency surface wave sustained plasma has been investigated. The radiative UV power has been obtained from optical absorption spectroscopic measurements of the Xe resonance level population and from Monte Carlo calculations of the effective decay rate of this level. Precise measurements of the rf power absorbed by the plasma enable the determination of the absolute vacuum ultraviolet discharge efficiency for the Xe surface wave discharge. Results show efficiencies up to more than 80(±11)&percent; . ©1997 American Institute of Physics.