Purification techniques and purity and density measurements of high-pressure Xe

A xenon gas purification system and simple techniques for purity and density measurements of high-pressure (∼60 atm) Xe have been developed. The purification system features two stages. As a first stage of purification an oxisorb and a high-temperature getter are used to purify Xe gas up to a level of that typically required for liquid Xe detectors. As a second stage, a titanium spark purifier is employed to further improve the purity by an order of magnitude. A gridded ionization chamber is used to measure the purity level and density of the xenon. The duration of pulses produced by cosmic muons inside the chamber gives the lower limit of an electronʹs life time. The capacitance between the mesh and anode, which depends on the dielectric constant of Xe, provides a temperature independent measurement of the density. This work is a part of a development program of high-pressure Xe detectors for hard X-ray and low energy gamma-ray astronomy.