Observation of Low- and High-Energy Gamow-Teller Phonon Excitations in Nuclei

Y. Fujita et al. ; 5 pags. ; 3 figs. PACS numbers: 24.30.Cz, 25.55.Kr, 27.40.+z

High-resolution study ofTz=+2→+1Gamow-Teller transitions in the44Ca(3He,t)44Sc reaction

Experimental study of Gamow-Teller transitions via the high-energy-resolution O18(He3,t)F18 reaction: Identification of the low-energy “super” -Gamow-Teller state

TheNd150(He3,t) andSm150(t,He3) reactions with applications toββdecay ofNd150

The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{b…

High-resolution study of Gamow-Teller transitions in the47Ti(3He,t)47V reaction

In this work we have studied ${T}_{z}=+2\ensuremath{\rightarrow}+1$, Gamow-Teller (GT) transitions in the $^{48}\mathrm{Ti}(^{3}\mathrm{He},t)^{48}\mathrm{V}$ charge-exchange reaction at 140 MeV/nucleon and ${0}^{\ensuremath{\circ}}$ at the Research Center for Nuclear Physics, Osaka. From the high-resolution facility, consisting of a high-dispersion beamline and the Grand Raiden spectrometer, the spectrum had an energy resolution of 21 keV, among the best achieved. Individual GT transitions were observed and GT strength was derived for each state populated up to an excitation energy of 12 MeV. The total sum of the $B$(GT) strength observed in discrete states was 4.0, which is 33% of the sum…

High-resolution study of Gamow-Teller excitations in theCa42(He3,t)Sc42reaction and the observation of a “low-energy super-Gamow-Teller state”

Y. Fujita et al.; 15 pags.; 6 figs.; 7 tabs.; PACS number(s): 21.10.Hw, 25.55.Kr, 27.40.+z, 25.40.Ep

Gamow-Teller transitions in theA=40isoquintet of relevance for neutrino captures inAr40

Background: The Gamow-Teller response of $^{40}\mathrm{Ar}$ is important for the use of liquid argon as a medium for neutrino detection. An ambiguity about the Gamow-Teller strength for the excitation of ${1}^{+}$ states at 2290 and 2730 keV in $^{40}\mathrm{K}$ results in a significant uncertainty for neutrino capture rates. This ambiguity is caused by the large discrepancy observed between strengths extracted from $^{40}\mathrm{Ar}$($p$, $n$) charge-exchange data and the transition strengths for the analog transitions studied in the $\ensuremath{\beta}$ decay of $^{40}\mathrm{Ti}$.Purpose: This study was aimed at resolving the ambiguity between the results from the $^{40}\mathrm{Ar}$($p$,…