Directional neutrino detection: from characterizing the cosmic neutrino background to imaging nuclear reactors

I will discuss two exciting prospects for future neutrino measurements.  New technological advancements make neutrino capture on tritium a promising path forward towards the detection of the CvB.  I will show that gravitational focusing by the Sun causes the expected neutrino capture rate to modulate annually. The amplitude and phase of the modulation depend on the phase-space distribution of the local neutrino background, which is perturbed by structure formation. Gravitational focusing is the only source of modulation for neutrino capture experiments, in contrast to dark-matter direct-detection searches where the Earth’s time-dependent velocity relative to the Sun also plays a role.  I will also show that CvB observatories may measure anisotropies in the cosmic neutrino velocity and spin distributions by polarizing the tritium targets.  

In the second part of my talk, I will propose the first truly directional antineutrino detector for antineutrinos above the hydrogen inverse beta decay threshold, with potential applications including monitoring for nuclear nonproliferation, spatially mapping geo-neutrinos, characterizing the diffuse supernova neutrino background, and searching for new physics in the neutrino sector. The design is a straightforward modification of existing antineutrino detectors; a prototype could be built with existing technology.