Speaker
Description
Thanks to their sub-keV energy threshold and excellent background discrimination, liquid xenon (LXe) dual-phase time projection chambers (TPCs) are the leading technology in the search for GeV-scale WIMP dark matter. However, these same properties also make them well suited not only for WIMPs, but for detecting other rare and faint phenomena, such as the coherent elastic neutrino-nucleus scattering (CEvNS) of solar neutrinos
In this talk we present the first measurement of solar $^8$B neutrinos through CEvNS in the XENONnT experiment, a dual-phase TPC with a LXe target volume of 5.9 tonne, located at the Laboratori Nazionali del Gran Sasso (LNGS). The measurement was performed through a dedicated low energy blind analysis, using an exposure of 3.51$\,\mathrm{tonne}\cdot\mathrm{year}$. The background only hypothesis was rejected with 2.73 sigma, resulting in a measured $^8$B flux of ($4.7^{+3.6}{−2.3})\cdot10^{-6}\mathrm{cm}^{−2}\mathrm{s}^{−1}$. This result represents not only the first measurement of CEvNS in LXe, but also the first observation of CEvNS from solar neutrinos in general. It thus marks an important milestone toward a future liquid xenon observatory—not only for dark matter detection, but also for exploring solar and neutrino physics at lowest energies.
