Ultraviolet discharges from a radio-frequency system for potential biological/chemical applications

In this work, we describe a new electrode-less radio-frequency (RF) excitation technique for generating excimers in the vacuum ultraviolet (VUV) and ultraviolet (UV) spectral regions for potential biological/chemical applications. Spectra data of Xe${}_2^{\ast }$, XeI${}^{\ast }$, and KrI${}^{\ast }$ generated by this new technique are presented. Optical efficiency of the lamp system ranges from 3% to 6% for KrI${}^{\ast }$, 7% to 13% for XeI${}^{\ast }$, and 15% to 20% for Xe${}_2^{\ast }$. Also, results of irradiating E-coli with XeI${}^{\ast }$ discharge from this lamp system is presented to show one of the promising applications of such electrode-less apparatus. This new RF lamp system offers an interesting addition to the already existing technologies for generating VUV and UV light for various biological, physical, and chemical processes especially those requiring large area for high productivity. (paper)