Dylan Yurgionas with Dan Akerib and Tom Shutt

Modeling Gamma Ray Background from LUX

Characterization of background is important for finding WIMP recoil events. Based on their cross sections, WIMPs will only scatter once inside the two phase xenon detector, LUX.  Incident gamma rays from trace radioactive impurities in detector components and surrounding materials produce background events in the detector. Gamma rays produced from these radioimpurities primarily photoabsorb and Compton scatter off xenon atoms. Backgrounds usually scatter more than once since their interaction length is a fraction of the linear dimension of the detector. Due to the relative abundance of gamma rays and that they mostly scatter multiple times they are an easily tagged high statistics population of events that can be used to describe the background environment in the WIMP search. A model of the observed background for multiple-scattered events will be produced and compared against the simulated data from known and estimated sources of backgrounds. A single model of gamma ray emission must be able to describe both the single- and multiple-scatter events. From this the sources of the gamma rays can be described and modifications of the current model can be made to lower background.