XENON was on the agenda at the European Physical Society Conference on High Energy Physics 2019 (EPS-HEP2019), which was held in Ghent, Belgium in the middle of July. The talk, presented by Adam Brown from the University of Zurich group, concentrated on results from XENON1T and also provided an overview of the work which is well underway to build the next generation detector, XENONnT.
Among results shown were our searches for elastic WIMP scattering and the recently published observation of double electron capture in 124Xe. The slides can be downloaded here. While the XENONnT upgrade currently in progress at Gran Sasso features many improvements of the XENON1T detector, Adam summarized four major improvements in one colorful slide.
Two members of the University of Zurich group gave talks on XENON1T at the annual meeting of the Swiss Physical Society in Lausanne, Switzerland. Chiara Capelli presented the latest news from the experiment and in particular the recently presented limit on spin-independent WIMP-nucleon cross-section, while Adam Brown spoke about the ongoing work searching for the inelastic scattering of WIMPs.
One of the key slides from Chiara’s talk is below. In the top-right you can see the WIMP-search data pre-unblinding, and in the bottom-right the efficiency for detecting nuclear recoils which happen in our fiducial volume. In the full talk, which is available here, she also presented the final limit and then gave a update on the preparations for the detector upgrade to XENONnT which are ongoing at the University of Zurich.
Adam’s talk focussed instead on an alternative possibility of searching for WIMPs via their inelastic scattering off xenon nuclei. During the interaction the nucleus is excited, and so the usual nuclear recoil signal would be observed in coincidence with the 39.6 keV gamma ray from the de-excitation of the nucleus. One of the attractions of this search channel, which is however less sensitive than elastic scattering, is that it distinguishes between spin-dependent and spin-independent WIMP interactions: a spin-dependent interaction is needed to change the nuclear spin state during its excitation. Again, the full talk is available online here.