The Next White (NEW) detector

TL;DR

The NEXT-White detector is the largest high-pressure xenon gas TPC with electroluminescent amplification, serving as a scale model for the NEXT-100 experiment searching for neutrinoless double beta decay in 136Xe.

Contribution

This paper details the design, infrastructure, and operation of the NEXT-White detector, a large-scale xenon TPC serving as a prototype for future neutrinoless double beta decay searches.

Findings

Operational since 2017 at LSC in Spain.

Successful measurement of event energy and track reconstruction.

Demonstrated high gas purity and electron lifetime.

Abstract

Conceived to host 5 kg of xenon at a pressure of 15 bar in the fiducial volume, the NEXT- White (NEW) apparatus is currently the largest high pressure xenon gas TPC using electroluminescent amplification in the world. It is also a 1:2 scale model of the NEXT-100 detector scheduled to start searching for $\beta\beta 0\nu$ decays in 136Xe in 2019. Both detectors measure the energy of the event using a plane of photomultipliers located behind a transparent cathode. They can also reconstruct the trajectories of charged tracks in the dense gas of the TPC with the help of a plane of silicon photomultipliers located behind the anode. A sophisticated gas system, common to both detectors, allows the high gas purity needed to guarantee a long electron lifetime. NEXT-White has been operating since October 2017 at the Canfranc Underground Laboratory (LSC), in Spain. This paper describes the detector and associated infrastructures.