Design and Characterization of a Neutron Calibration Facility for the Study of sub-keV Nuclear Recoils
Abstract
As part of an experimental effort to demonstrate sensitivity in a large-mass detector to the ultra-low energy recoils expected from coherent neutrino-nucleus elastic scattering, we have designed and built a highly monochromatic 24 keV neutron beam at the Kansas State University Triga Mark-II reactor. The beam characteristics were chosen so as to mimic the soft recoil energies expected from reactor antineutrinos in a variety of targets, allowing to understand the response of dedicated detector technologies in this yet unexplored sub-keV recoil range. A full characterization of the beam properties (intensity, monochromaticity, contaminations, beam profile) is presented, together with first tests of the calibration setup using proton recoils in organic scintillator.