SuNSCREEN: A cosmic-ray veto detector for capture-reaction measurements

The Summing NaI(Tl) detector (SuN) is used in nuclear astrophysics experiments measuring (p,γ) and (α,γ) reactions. The main background in these experiments in the energy region of interest comes from cosmic rays. The Scintillating Cosmic Ray Eliminating Ensemble (SuNSCREEN) was developed to be combined with the SuN detector to increase the sensitivity of reaction cross-section measurements by reducing the cosmic-ray background. SuNSCREEN is a plastic scintillating array consisting of 9 bars, which are positioned in a roof-like configuration above SuN. A significant reduction of the background was observed in the energy region of interest.