Position uncertainties of AGATA pulse-shape analysis estimated via the bootstrapping method

The unprecedented capabilities of state-of-the-art segmented germanium-detector arrays, such as AGATA and GRETA, derive from the possibility of performing pulse-shape analysis. The comparison of the net- and transient-charge signals with databases via grid-search methods allows the identification of the $$\gamma $$ γ -ray interaction points within the segment volume. Their precise determination is crucial for the subsequent reconstruction of the $$\gamma $$ γ -ray paths within the array via tracking algorithms, and hence the performance of the spectrometer. In this paper the position uncertainty of the deduced interaction point is investigated using the bootstrapping technique applied to $$^{60}$$ 60 Co radioactive-source data. General features of the extracted position uncertainty are discussed as well as its dependence on various quantities, e.g. the deposited energy, the number of firing segments and the segment geometry.

Study of the high energy neutron flux (15-20 MeV) using a BC501A liquid scintillator

An experiment was conducted in order to characterize the neutron beam between ~15-20 MeV, at the 5.5 MeV tandem T11/25 Accelerator of NCSR ‘‘Demokritos’’. A liquid scintillator, BC501A, was used due to its n-γ discrimination capability and a versatile pulse shape analysis was applied. Offline, the discrimination circuit was tested for tolerance in high counting rates and sensitivity in lowering the limit of the neutron energy monitored through the threshold of the processed signal. The employed circuit proved to be very sensitive to changes in the latter. Neutron spectra at the energies of 14.8, 16.6, 19.2 and 20 MeV were acquired and the unfolding process using the DIFBAS code is currently in progress. Their deconvolution is expected to reveal the extent of the presence of low-energy parasitic neutrons.