The γ-decay of the [formula omitted] and 2p inner-hole states in 111Sn via the 112Sn( 3He, αγ) reaction at 32 MeV

Abstract

The γ-decay of the deeply-bound hole states in 111Sn has been investigated at 32 MeV incident energy by means of the 112Sn( 3He, αγ) reaction. The α-particles emitted near 0° were detected in a Si counter located at the image plan of the superconducting solenoidal spectrometer SOLENO. The γ-rays in coincidence with the α-particles were detected by two Ge(Li) detectors located at 90° and 142° with respect to the beam direction, respectively. Energies, spins and decay schemes have been established for the low-lying states up to 2.5 MeV excitation energy in 111Sn. The γ-decay of the broad bump, located around 4.2 MeV and previously attributed to neutron pick-up from the inner 1 g 9 2 , 2 p 1 2 , and 2 p 3 2 neutron. Subshells, reveals the importance of quasiparticle-phonon m the spreading mechanism of the inner-hole strengths. The 1 g 9 2 and 2p strength functions have been deduced from the α-decay of the enhanced structures (3 ≦ E x≦ 8 MeV). They are compared to the ones measured in previous inclusive neutron pick-up experiments and to those calculated in the framework of the quasiparticle-phonon nuclear model.