The nuclear deformation versus the spin-flip like excitations and the suppression of the 2νββ decay amplitude

✍ Scribed by A.A. Raduta; D.S. Delion; Amand Faessler

• Book ID: 104336298
• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 962 KB
• Volume: 617
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/s0375-9474(97)00039-0

✦ Synopsis

The suppression mechanism of the Gamow-Teller double beta decay amplitude M6-r is studied using a many body Hamiltonian which describes a composite system of protons and neutrons moving in a projected spherical single particle basis, Alike nucleons interact through pairing while protons and neutrons by a separable dipole-dipole force both in the particle-hole (ph) and particle-particle (pp) channels. The spin-flip and non-spin-flip components of the QRPA phonons have a differents contribution to the MeT values. The relative magnitudes and phases depend both on the strength of the particle-particle interaction (gpp) and on the nuclear deformation. The deformation yields a fragmentation of the MG-r value on one hand and washes out the separation of states of pure spin-flip and non-spin-flip structures. Due to this effect M~T has only one fragmented resonance structure in the low part of the spectrum.