High resolution ¹⁴⁸Nd(³He,nγ) two proton stripping reaction and the structure of the 0₂⁺ state in ¹⁵⁰Sm

¹ University of Western Cape, Department of Physics, P/B X17, Bellville, 7535, South Africa
² Stellenbosch University,Department of Physics, P/B X17, Matieland, 7602, South Africa
³ iThemba LABS,National Research Foundation, PO Box 722, Somerset-West 7129, South Africa
⁴ University of Johannesburg, Department of Physics, PO Box 524, Auckland Park 2006 South Africa
⁵ University of Zululand, Department of Physics, P/B X1001, Kwa Dlangezwa 3886, South Africa
⁶ University of Cape Town, Department of Physics, P/B X3, Rondebosch 7701, South Africa

^a Corresponding author: jfss@tlabs.ac.za

Published online: 3 April 2014

Abstract

The challenge of achieving high resolution in binary reactions involving an outgoing high energy neutron is solved by detecting the γ-ray decay of populated excited states in an array of escape suppressed HPGe detectors in coincidence with fast neutrons detected in a wall of scintillator detectors 2m down beam of the target. The selectivity of the arrangement is of the order of 1 in 1000. The time-of-flight difference is sufficient to separate fast neutrons from direct reactions from a large background of statistical neutrons from fusion-evaporation reactions. Our interest is in the wavefunction of the 0₂⁺ state at 740 keV in the N=88 nucleus ¹⁵⁰Sm which, with the 0₂⁺ state in ¹⁰⁰Ru, are the only two excited states observed in 2β2ν double β-decay.