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Description
In this work, three novel EJ-309-type liquid organic scintillators and one BC-501A scintillator were optimized for measurements of neutron elastic scattering $(n,\mathrm{el})$ and inelastic scattering $(n,\mathrm{inl})$ at NCSR "Demokritos". These four liquid scintillators were arranged in a new configuration at eight representative Legendre angles, specifically at $16.2^\circ$, $37.2^\circ$, $58.3^\circ$, $79.4^\circ$, $100.6^\circ$, $121.7^\circ$, $142.8^\circ$, and $163.8^\circ$. The total elastic cross section can be accurately determined by measuring the differential elastic cross section at these angles. The array was designed taking into account detector shielding requirements, minimizing detector cross-talk, and reducing scattering angle uncertainty, while ensuring maximum possible statistics. For accurate elastic cross-section measurements, pulse shape analysis (PSA) was initially performed to discriminate neutrons from gamma rays over a broad energy range. For this purpose, a semi-digital unit, MPD-4 from Mesytec, was used to carry out the PSA and to optimize the parameters for neutron--gamma $(n$--$\gamma)$ discrimination, using an $Am-Be$ $n/\gamma$ source, along with a set of $^{137}\mathrm{Cs}$, $^{54}\mathrm{Mn}$, and $^{60}\mathrm{Co}$ gamma-ray sources. To assess the detector efficiency over a wide neutron energy range, particularly between 1 and 6 MeV, GEANT4 simulations are currently in progress. In the coming months, the validity of the procedure will be evaluated by reproducing the well-established total cross-section value of $^{12}\mathrm{C}(n,\mathrm{el})$ scattering.