Extended Data Fig. 2: Energy resolution.
From: Observation of two-neutrino double electron capture in 124Xe with XENON1T
Ratio of the mean peak energy (μE) to the peak width (σE) for low-energy monoenergetic lines in selected LXe dark-matter experiments (LUX38 and XENON10039) and in the 1.5-t fiducial mass of the XENON1T detector. The relative resolution is defined as the σE/μE ratio of the Gaussian lines and is fitted using a phenomenological function (solid blue line). For XENON1T the data points are 83mKr (41.5 keV), 131mXe (163.9 keV), 129mXe (236.2 keV), 214Pb (351.9 keV) and 208Tl (510.8 keV). Only statistical uncertainties are shown for XENON1T (smaller than the markers). The energy of the 2νECEC peak is indicated by the black dashed line.
