  We demonstrate excitation of metastable krypton and xenon beams using a
vacuum ultraviolet lamp and directly compare the performance of this method to
metastable excitation based on a radiofrequency-driven plasma discharge. In our
apparatus, lamp-based metastable excitation outperforms the plasma discharge
across a wide range of beam flux values relevant for Atom Trap Trace Analysis
(ATTA). Moreover, we do not observe significant degradation in lamp performance
after over 160 hours of operation. We find that lamp-based excitation is
particularly advantageous at the smallest and largest beam fluxes tested,
demonstrating the utility of this approach both for improving krypton ATTA and
for enabling the detection of radioactive xenon isotopes using ATTA. Finally,
we demonstrate an additional enhancement to lamp-based metastable excitation
efficiency and stability by applying an external magnetic field.
