DAPPER is the Detector Array for Photons, Protons, and Exotic Residues. It was fabricated at Texas A&M University Cyclotron Institute and commissioned in 2021. DAPPER is designed to measure products from (d,p) reactions in inverse kinematics. From the proton kinetic energy, DAPPER measures the excitation energy; with a high-efficiency array of 128 BaF2 scintillators, DAPPER measures the gamma ray multiplicity, total gamma ray energy, and the energy of each gamma ray. From these data, the photon strength function is extracted. The (d,p) is a proxy reaction that allows measurement on nuclei for which the (n,g) reaction is not possible to measure. The data DAPPER provides constrains predictive models of neutron capture, which have applications in nuclear astrophysics, advanced reactor design, and national security.

Publications

Development of the detector array for photons, protons, and exotic residues, A. B. McIntosh et al., Nucleus-Nucleus 2024, Nuclear Physics A 1057, Whistler, BC, Canada, pages 123038, 2025

Using DAPPER to extract the photon strength function of ⁵⁸Fe using the inverse Oslo and shape methods, A. D. Abbott, Physical Review C 111, 034322 (2025)

Study of ⁵⁸Fe’s Photon Strength Function via (d,p) Reaction in Inverse Kinematics Using a Forward Method, Maxwell Q. Sorensen, Ph.D. Thesis, TAMU, 2024

Using DAPPER to Extract the Photon Strength Function of ⁵⁸Fe via the Inverse Oslo and Shape Methods, Austin D. Abbott, Ph.D. Thesis, TAMU, 2024