2005/12/31 by R. G. T. Zegers, H. Akimune, Sam M. Austin +41 · 4 citations
Physics and Astronomy · #Atomic and Molecular Physics #Nuclear physics research studies #Quantum Chromodynamics and Particle Interactions #nucl-ex
paper · pdf · doi:10.1103/physrevc.74.024309
published as Phys.Rev.C74:024309,2006 · 16 pages, 6 figures
arxiv created 2006/03/20 · openalex publication_date 2006/08/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
It is shown via a study on a 26Mg target that the (t,3He) reaction at 115 MeV/nucleon reaction is an accurate probe for extracting Gamow-Teller transition strengths. To do so, the data are complemented by results from the 26Mg(3He, t) reaction at 140 MeV/nucleon that allows for a comparison of T=2 analog states excited via the mirror reactions. Extracted Gamow-Teller strengths from 26Mg(t,3He) and 26Mg(3He, t) are compared with those from 26Mg(d,2He) and 26Mg(p,n) studies, respectively. A good correspondence is found, indicating probe independence of the strength extraction. Furthermore, we test shell-model calculations using the new USD-05B interaction in the sd-model space and show that it reproduces the experimental Gamow-Teller strength distributions well. In anticipation of further (t,3He) experiments on medium-heavy nuclei aimed at determining weak-interaction rates of relevance for stellar evolution, a second goal of this work is to improve the understanding of the (t,3He) and (3He, t) reaction mechanisms at intermediate energies because detailed studies are scarce. The distorted-wave Born approximation is employed, taking into account the composite structures of the 3He and triton particles. The reaction model provides the means to explain systematic uncertainties at the 10%--20% level in the extraction of Gamow-Teller strengths as being because of interference between Gamow-Teller \ensuremathΔL=0,\ensuremathΔS=1 and \ensuremathΔL=2,\ensuremathΔS=1 amplitudes that both contribute to transitions from 0+ to 1+ states.