FAST spectrometer beam test data

This dataset contains the results from beam tests of the FAST spectrometer system conducted at the Back-n beamline of the China Spallation Neutron Source (CSNS). The measurements include neutron reaction rate spectra, pile-up ratings, and neutron transmission data obtained using a 10 mm thick natural lead (Pb) sample. The tests were performed under two beam spot sizes (12 mm and 3 mm), and the corresponding total neutron cross sections are provided. These data support the evaluation and optimization of the spectrometer’s performance in mixed-field neutron environments.