Influence of 5~10 MeV γ background on measurements of astrophysical reactions at the JUNA facility

Cross-sections of charged particle induced reactions in the energy region of astrophysics interest (Gamow window) are extremely low, thus measurements of these reactions in aboveground laboratory will be severely disturbed by background induced by cosmic rays．The main way to solve this problem is to measure these reactions in an underground laboratory．The Jinping Underground Nuclear Astrophysics (JUNA) experimental facility is the first underground nuclear astrophysical facility in China, the facility is superb to study key reactions of astrophysical importance. Backgrounds of BGO detector array and LaBr₃ detector were measured at JUNA and compared with those measured aboveground．It was found that background from 5-10 MeV could be further suppressed by reducing coincidence window, selecting fire number, and by removing α particle signals with pulse-shape discrimination．Possible influence of current background on several planned reaction measurements at JUNA has been evaluated．