The e−e+ decay of the candidate new particle X(17) has already been confirmed by previous experiments. However, theoretical models give different predictions for the spin and the parity of this particle. The double γ-decay process could be an appropriate probe to shed light on such properties. Thus, for the first time, we searched for the γγ decay of X(17) created in nuclear transitions. In this paper, we report preliminary results of two experiments on the Jπ = 0− → 0+ transition in 4He.
Nagy, A.; Krasznahorkay, A.J.; Csatlós, M.; Csige, L.; Gácsi, Z.; Hunyadi, M.; Sas, N.; Timár, J.; Tornyi, T.; et al.:
Searching for the double gamma-decay of the X(17) particle.
Nuovo Cimento C-Colloquia and Communications in Physics 42 (2019) 124.
Published: 5 February 2019