A proposed dark matter detector based on scintillation pulse shape differences in high pressure Xe gas

We propose a dark matter detector based on high pressure gas scintillation (HPGS) using Xe as the target gas. Scintillation pulse time constants in Xe gas are an order of magnitude longer for alpha particles than for electron recoils from gammas or betas. If alpha particle pulses are typical also of recoils for heavier nuclei this offers the possibiklity of a room temperature dark matter detector which could be simpler and lower cost than detectors based on liquid xenon, liquid argon, or mK bolometric techniques. Background estimates for Xe gas detectors operating at 5–10 bar show that a single 34 kg detector module could reach a dark matter cross section sensitivity 1E−9 pb, and an array of 15–30 such detectors of total mass 500 kg–1000 kg could reach < 1E−10 pb.