Krasznahorkay, AttilaSadoun, Nermin Kamal Abdelhamid2020-05-142020-05-142020-05-14http://hdl.handle.net/2437/287361The purpose of this thesis is figuring out the properties of X17 particle by searching for the γγ decay of this particle produced in nuclear transitions. The coincident double γ radiation of an electromagnetically forbidden , 0 − → 0 + , transition of helium-4 ( 4 He) is studied in order to distinguish between the vector or the pseudoscalar boson scenario.26enX17scintillatorLaBr3DEENK Témalista::Fizika