Search for nucleon decays with EXO-200

TL;DR

This paper reports on a search for nucleon decay in xenon-136 using the EXO-200 detector, setting new lifetime limits that surpass previous bounds by significant factors.

Contribution

The study provides the most stringent limits to date on nucleon decay in xenon-136, improving previous bounds by factors of 9 and 7.

Findings

Lifetime limits of 3.3×10^{23} years for decay to $^{133}$Sb.

Lifetime limits of 1.9×10^{23} years for decay to $^{133}$Te.

Exceeds prior decay limits by factors of 9 and 7.

Abstract

A search for instability of nucleons bound in $^{136}$Xe nuclei is reported with 223 kg$\cdot$yr exposure of $^{136}$Xe in the EXO-200 experiment. Lifetime limits of 3.3$\times 10^{23}$ and 1.9$\times 10^{23}$ yrs are established for nucleon decay to $^{133}$Sb and $^{133}$Te, respectively. These are the most stringent to date, exceeding the prior decay limits by a factor of 9 and 7, respectively.