NPC Neutrino Seminar

Doping liquid argon with xenon in ProtoDUNE-SP

by Niccolo Gallice (BNL)

Zoom + West Wing (WH 10W)

Zoom + West Wing (WH 10W)


Doping liquid argon with xenon is an advantageous technique for shifting the wavelength of scintillation light to enhance light collection. From February to May 2020, a specialized run was conducted in the single-phase DUNE Far Detector prototype (ProtoDUNE-SP) at CERN, involving 770 tons of total liquid argon mass, with 410 tons of fiducial mass. The test involved injecting up to 18.8 ppm of xenon into the detector to measure the light and charge response. This test marked a milestone for the LAr-TPC (Liquid Argon Time Projection Chamber) community, as it was the first large-scale xenon doping ever performed. The seminar will briefly present the experimental setups used, starting with ProtoDUNE-SP and continuing to a dedicated subsystem installed specifically for this run. Subsequently, it will illustrate the current understanding of the underlying physics of the argon-to-xenon energy transfer and shifting mechanisms, including the impact of nitrogen presence in argon. Results from both setups are presented to highlight the effectiveness of the doping and the overall advantages for light collection. The dedicated setup managed to detect the light coming from xenon, proving the concept and monitoring the doping stability over time. Additionally, it was shown that introducing xenon can mitigate light loss due to nitrogen contamination. Data from ProtoDUNE-SP then assessed that the light collection uniformity improves as xenon is added to the mixture. These findings pave the way for further exploration and optimization of xenon doping techniques, with implications for a range of applications in neutrino physics and beyond.