New Xenon-Light Source for the Vacuum Ultraviolet*

TLDR

Xenon’s molecular continuum, mainly from the 3Σu+→1Σg+ transition, underlies VUV emission. A new vacuum ultraviolet light source is described that emits a strong continuous spectrum from 1500 Å to 2250 Å. The source is a sealed Pyrex tube charged with xenon, fitted with a fluorite window, and excited by 2450 MHz microwave energy to produce the continuous VUV spectrum. It successfully captured the Schumann‑Runge absorption bands of oxygen using a 21‑foot vacuum grating spectrograph.

Abstract

A new vacuum ultraviolet-light source is described which emits a strong continuous emission spectrum from 1500A to 2250A. This source is constructed of Pyrex, is charged with xenon, and carries a fluorite window which allows the tube to be completely sealed off from the vacuum system. Microwave energy at a frequency of 2450 mc/sec is used to excite the emission. Molecular xenon is presumably responsible for the continuum and the main transition is probably 3∑u+→1∑g+ with some contribution from 1∑u+→1∑g+. The source has been used to photograph the Schumann-Runge absorption bands of oxygen in the first order of a 21-foot vacuum grating spectrograph.