Optical Properties of Liquid Noble Gas Scintillators
Dr. Alexander Neumeier (Physik-Department E15, TUM)
Liquid noble gases, liquid argon and liquid xenon in particular, have many applications in rare event phyiscs such as direct dark matter search, neutrinoless double-beta decay, and high-energy neutrino physics. Due to their high scintillation efficiency and their ability to be cleaned chemically to a high level of purity, they are a very attractive detector material. The main part of the talk will focus on a recent discovery of intense infrared (IR) emission in liquid argon doped with a small amount of xenon. The different measurement techniques in the vacuum ultraviolet (VUV) and the infrared region (IR) will be presented. Wavelength and time resolved emission spectra of xenon-doped liquid argon in the VUV and in the IR under electron-beam excitation will be presented. A tentative assignment of the IR emitting species using complementary absorption information will be given. Using both the VUV and the newly found IR emission simultaneously will be discussed as a new detector concept. Earlier work of our group concerning the scintillation properties of pure liquid argon will be compared with the results from xenon-doped liquid argon. Wavelength and time resolved emission spectra of pure liquid argon under electron and ion-beam excitation will be presented.