Spectroscopic studies on the beta-delayed neutron emission of ⁵³K

An experimental study on the β-n spectroscopy of ⁵³K was carried out at the ISOLDE Decay Station (IDS). This neutron-rich isotope has a large Q_β value (energy window available for the β decay) and low neutron-separation energy (S_n) in the daughter (⁵³Ca), making it an ideal case for detailed studies of β-n process, similar to the ¹³⁴In decay [1]. In this work, we measured the β decay of ⁵³K in the coincidence of γ-ray and neutron-time-of-flight (nTOF) spectroscopy using HPGe and INDIe [2] arrays respectively at IDS. In this contribution, I will present the latest results from the experiment, mainly focusing on the apparent beta feeding (I_β) of the ⁵³K decay. In addition, exclusive neutron-emission branching ratios following β decay will be discussed. The experimental findings are compared with the shell-model calculations and Hauser-Feshbach statistical models, providing valuable insights into the β-decay and β-n process far from the stability line and into their connections to the neutron shell gap at N=34.

[1] J. Heideman et al, being reviewed by Phys. Rev. Lett.

[2] M. Madurga et al, Phys. Rev. Lett 117, 092502 (2016).