Electronic-Recoil Excess in XENON1T

• Sara Diglio (Subatech)

With the lowest background level ever reached by a liquid xenon time projection chamber, XENON1T proved to be the most sensitive WIMP dark matter direct detection experiment on earth. Despite being primarily designed to search for nuclear recoils between WIMPs and xenon atoms, the unprecedented low electron recoil background of (76 ± 2) stat events/(tonne × year × keV) between 1–30 keV, made the XENON1T experiment suitable also to explore new parameter space for electronic-recoil channels. In this talk, I will review the XENON1T detection principles before focusing on the recently observed electronic recoil excess in the (1 - 7) keV region. I will discuss the different interpretations of this excess, provide details on the analysis, and cross-checks of our results.