Measurement of Light Yield Response of Gd-compatible Water-based Liquid Scintillator with the Brookhaven 1-ton testbed

The Water-based Liquid Scintillator (WbLS) enables hybrid detection by combining scintillation and Cherenkov signals, providing superior event reconstruction capabilities compared to conventional neutrino detectors. We measured the light yield of Gd-compatible WbLS at varying concentrations from 0.35% to 1% by mass, using cosmic-ray muons in a 1-ton scale detector at BNL. The light yield is measured as (69.16 ± 6.92) ph / MeV at 0.35% concentration, which increased to (87.32 ± 8.73) ph / MeV at 1%. These results establish a quantitative basis for optimizing future WbLS-based detectors in neutrino physics.