Speaker
Description
Heavy ion charge exchange reactions are of manyfold interest for nuclear reaction and structure physics. In a recent paper [1] a fully microscopic theory of heavy ion single charge exchange (SCE) reactions was formulated. Here, a new theoretical approach is presented, emphasizing the role of single and double charge exchange reactions for probing nuclear response functions of the same type as encountered in single and double beta decay [2]. In particular, a special class of nuclear double charge exchange (DCE) reactions proceeding as a one-step reaction through a two-body process are shown to involve nuclear matrix elements of the same diagrammatic structure as in $0\nu 2\beta$ decay. These correlated Majorana-DCE (MDCE) reactions are distinct from second order DCE reactions which are characterized the best as sequential double single charge exchange (DSCE), thus carrying a close resemblance to $2\nu 2\beta$ decay. The results suggest that ion-ion DCE reactions are the ideal testing grounds for investigations of double-beta decay nuclear matrix elements as proposed by the NUMEN project [3]. Nuclear response functions for $\tau_\pm$ excitations and applications to recent single and double charge exchange data measured by the NUMEN collaboration at LNS Catania are discussed.
References:
[1] H.~Lenske, J.~I.~Bellone, M.~Colonna and J.~A.~Lay,
Phys. Rev. C 98 (2018) 044620
[2] H.~Lenske,
J.Phys.Conf.Ser. 1056 (2018) 012030.
[3] F.~Cappuzzello et al.,
Eur. Phys. J. A 54 (2018) 72
