Detection of liquid xenon scintillation light with a silicon photomultiplier

We have studied the feasibility of a silicon photomultiplier (SiPM) to detect liquid xenon (LXe) scintillation light. The SiPM was operated inside a small volume of pure liquid xenon (LXe), at -95∘C, irradiated with an internal 241Am αα source. The gain of the SiPM at this temperature was estimated to be 1.8×1061.8×106 at a 52 V bias voltage. Based on the geometry of the setup, the quantum efficiency of the SiPM was estimated to be 22% (5.5% is the photon detection efficiency) at the Xe wavelength of 178 nm. The low excess noise factor (about 1.05), high single photoelectron detection efficiency, and low bias voltage of SiPMs make them attractive alternative UV photon detection devices to photomultiplier tubes (PMTs) for liquid xenon detectors, especially for experiments requiring a very low energy detection threshold, such as neutralino dark matter searches.