Towards the optimal performance of Mazinger, a shallow γ-ray spectrometry system of high efficiency and very-low-level background, devoted to 210Pb and U–Th dating for paleoclimatic applications

Precise radionuclide measurements are crucial for absolute dating in paleoclimatic studies. Mazinger, a very-low-level background and high-efficiency γ -ray spectrometer, was upgraded with two anti-muon veto detectors and its acquisition electronics have been reconfigured, both to improve detection limits and handle higher event rates coming from the veto system. The upgrade led to a doubling of Mazinger’s figure of merit and significantly reduce the background level. These improvements enhance Mazinger’s performance for geochronological applications. Application to 210 Pb dating of a low-level activity sediment core from Sobrado Lagoon (Spain) produced an age model with uncertainties under 5%, matching correctly with the 137 Cs profile.