Speaker
Description
In the last years, double charge exchange (DCE) nuclear reactions have gained an increasing interest due to their close analogies to neutrinoless double beta ($0\nu\beta\beta$) decay [1]. On this ground, the NUMEN project [2] proposed an innovative method to deduce data-driven information on the nuclear transition matrix elements for the candidate isotopes to $0\nu\beta\beta$ decay by measuring DCE cross sections. In this context, the $^{18}$O $+$ $^{48}$Ti collision at 275 MeV incident energy was studied for the first time, with $^{48}$Ti being the daughter nucleus of $^{48}$Ca in the $0\nu\beta\beta$ process [3]. The measurements were performed at the INFN - Laboratori Nazionali del Sud in Catania, using the MAGNEX magnetic spectrometer [4]. A full understanding of DCE reactions is a complex task since different reaction mechanisms contribute to the measured DCE cross section. For this reason, a multi-channel approach is adopted, where DCE reactions are investigated not as stand-alone processes, but as a part of a network of nuclear transitions which includes elastic and inelastic scattering, one- and two-nucleon transfer reactions, and single charge exchange reactions [1,5]. The study of elastic and inelastic scattering gives access to the optical potential and nuclear deformations, respectively, which are key ingredients for the theoretical description of all the reaction channels [6]. The analysis of one-nucleon transfer reactions is fundamental to understand the degree of competition between the DCE process and successive nucleon transfer reactions, as well as to probe single-particle configurations in the nuclear many-body wave functions [7,8]. In this contribution, the status of the multi-channel study of the $^{18}$O $+$ $^{48}$Ti system will be presented.
[1] F. Cappuzzello et al., Prog. Part. Nucl. Phys. 128 (2023) 103999
[2] F. Cappuzzello et al., Eur. Phys. J. A 54 (2018) 72
[3] K. Tetsuno et al., J. Phys. Conf. Ser. 1468 (2020) 012132
[4] F. Cappuzzello et al., Eur. Phys. J. A 52 (2016) 167
[5] H. Lenske et al., Prog. Part. Nucl. Phys. 109 (2019) 103716
[6] G. A. Brischetto et al., Phys. Rev. C, accepted
[7] O. Sgouros et al., Phys. Rev. C 104 (2021) 034617
[8] O. Sgouros et al., Phys. Rev. C 108 (2023) 044611