Gamma decay of 39K levels measured with the 38Ar(p, γ) 39 reaction

Abstract

The 38Ar(p,γ) 39K reaction has been studied in the E p = 1.25–2.35 MeV range. The strengths of 41 resonances have been determined relative to the strength of a 36Ar(p,γ) 37K. resonance. The branching ratios often resonances and often bound states have been measured with a 50 cm 3 Ge(Li) detector; the reaction Q-value is Q = 6380.6 ± 1.2 keV. A spin J = 3 2 has been assigned to the 3.02, 4.08 and 7.74 MeV levels on the basis of angular distribution measurements. Doppler shift attenuation measurements have been performed on γ-rays deexciting the 2.52, 3.02 and 4.08 MeV levels. The 7.74 MeV state is interpreted as the analogue of the first excited state (E x = 1.2 MeV, J π = 3− 2 ) in 39Ar. The experimental properties of 39K levels are compared with recent shell-model calculations. The analogue to anti-analogue Ml strength is compared with the strengths of other similar transitions and with theoretical calculations.