Towards Probing the Diffuse Supernova Neutrino Background in All Flavors

Understand

Fully understanding the average core-collapse supernova requires detecting the diffuse supernova neutrino background (DSNB) in all flavors.

• While the DSNB $\bar{\nu}_e$ flux is near detection, and the DSNB $\nu_e$ flux has a good upper limit and prospects for improvement, the DSNB $\nu_x$ (each of $\nu_\mu, \nu_\tau, \bar{\nu}_\mu, \bar{\nu}_\tau$) flux has a poor limit and heretofore had no clear path for improved sensitivity.
• We show that a succession of xenon-based dark matter detectors -- XENON1T (completed), XENONnT/LUX-ZEPLIN (running), and DARWIN (proposed) -- can dramatically improve sensitivity to DSNB $\nu_x$ the neutrino-nucleus coherent scattering channel.
• XENON1T could match the present sensitivity of $\sim 10^3 \; \mathrm{cm}^{-2}~\mathrm{s}^{-1}$ per $\nu_x$ flavor, XENONnT/LUX-ZEPLIN would have linear improvement of sensitivity with exposure, and a long run of DARWIN could reach a flux sensitivity of $\sim 10 \; \mathrm{cm}^{-2}~\mathrm{s}^{-1}$.