Cherenkov and Scintillation Light Separation in Organic Liquid Scintillators

The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of \(338\pm 12\) ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of \(70 \pm 3 \%\) and \(63\pm 8\%\) for time- and charge-based separation, respectively, with scintillation contamination of \(36\pm 5\%\) and \(38\pm 4\)%. LAB/PPO data is consistent with a rise time of \(\tau _r=0.72\pm 0.33\) ns.