Measurement of the absorption length and absolute quantum efficiency of TMAE and TEA from threshold to 120 nm

The absorption length and absolute photoionization quantum efficiency of TMAE (tetrakis-dimethylamino-ethylene) and TEA (triethylamine) vapors have been measured in a wavelength interval from 120 to 280 nm. Both of these materials can serve as a photosensitive agent for ultraviolet photon detectors used in high energy and nuclear physics experiments and for medical imaging. The absorption length and absolute quantum efficiency are important parameters in the design of these detectors. We find that the quantum efficiency for TMAE has a peak of 58% at 146 nm and rises again toward shorter wavelengths. The TEA quantum efficiency reaches a peak of 33% at 153 nm and has a plateau of 17% below 135 nm. We fail to observe a second peak in TEA around 136 nm as has been previously reported. (orig.)