Electrode Design & Characterisation for the XLZD Observatory

The XLZD (XENON, LZ, DARWIN) collaboration aims to construct and operate the ultimate multi-tonne xenon-based direct detection astroparticle observatory. Hosting a time projection chamber (TPC) with more than 60 tonnes of liquid xenon, with a keV-range threshold and an ultra-low radioactive background it will aim to probe the entire parameter space for WIMP dark matter down to the so-called neutrino fog. XLZD scientific research program also includes searches for solar axions, axion-like particles, measurements of the solar neutrino flux and a probe of the Majorana nature of neutrinos.

High-voltage electrodes, spanning 3 m in diameter, will lie at the heart of the XLZD TPC, playing multiple key roles in signal generation and reconstruction. The electrodes need to be feasible to produce, mechanically robust, sufficiently transparent to light propagation and have minimal spurious electron and light emission from their surface.

An R&D program at KIT aims to tackle these challenges. We’ve developed several test setups aimed at studying emission from electrode samples and ways of mitigating it, as well as a high-voltage scanning system for electrodes. ... mehrHere, we will present our recent work on electrode R&D towards XLZD-scale electrodes. This work is supported in part through the Helmholtz Initiative and Networking Fund (grant agreement no. W2/W3-118) and by BMBF (ErUM-Pro, grant no. 05A23VK3).