Measurement of the Transverse Diffusion of Electrons in Liquid Xenon with the EXO-200 Detector

The EXO-200 Collaboration is searching for neutrinoless double beta decay using a liquid xenon (LXe) time projection chamber. This measurement relies on modeling the size of charge deposits produced by interactions in the LXe to allow discrimination between signal and background events. Electron diffusion increases the size of events and can reduce the effectiveness of this discrimination. This effect is small for the current experiment, but in the next-generation ton-scale detectors used for both dark matter and double beta decay this effect will be more important. Presented here is a measurement by EXO-200 of the transverse diffusion constant of electrons at low drift fields to help better understand the transport properties of electrons in liquid xenon.