Development of low-background photomultiplier tubes for liquid xenon detectors

Abstract

We successfully developed a new photomultiplier tube (PMT) with a three-inch diameter, convex-shaped photocathode, R13111. Its prominent features include good performance and ultra-low radioactivity. The convex-shaped photocathode realized a large photon acceptance and good timing resolution. Low radioactivity was achieved by three factors: (1) the glass material was synthesized using low-radioactive-contamination material; (2) the photocathode was produced with ${}^{39}$K-enriched potassium; and (3) the purest grade of aluminum material was used for the vacuum seal. As a result each R13111 PMT contains only about 0.4 mBq of ${}^{226}$Ra, less than 2 mBq of ${}^{238}$U, 0.3 mBq of ${}^{228}$Ra, 2 mBq of ${}^{40}$K and 0.2 mBq of ${}^{60}$Co. We also examined and resolved the intrinsic leakage of Xe gas into PMTs that was observed in several older models. We thus succeeded in developing a PMT that has low background, large angular acceptance with high collection efficiency, good timing resolution, and long-term stable operation. These features are highly desirable for experiments searching for rare events beyond the standard model, such as dark matter particle interactions and neutrinoless double beta decay events.

References in corpus (14)

• The Large Underground Xenon (LUX) Experiment
• The XENON1T Dark Matter Experiment
• XMASS detector
• Lowering the radioactivity of the photomultiplier tubes for the XENON1T dark matter experiment
• A direct dark matter search in XMASS-I
• Qualification Tests of the R11410-21 Photomultiplier Tubes for the XENON1T Detector
• Light WIMP search in XMASS
• An Ultra-Low Background PMT for Liquid Xenon Detectors
• Search for dark matter in the form of hidden photons and axion-like particles in the XMASS detector
• Direct dark matter search by annual modulation with 2.7 years of XMASS-I data
• Search for sub-GeV dark matter by annual modulation using XMASS-I detector
• Search for WIMP-${}^{129}$Xe inelastic scattering with particle identification in XMASS-I
• Development of low radioactivity photomultiplier tubes for the XMASS-I detector
• Performance of Photosensors in the PandaX-I Experiment

Cited by in corpus (2)

• Performance evaluation of the 8-inch MCP-PMT for Jinping Neutrino Experiment
• Development of a low-background HPGe detector at Kamioka Observatory