Exotic decay of ¹¹⁵Cs

Summary, in English

The detailed study of the β⁺/EC decay of the very neutron-deficient and alpha-unbound nucleus ¹¹⁵Cs is presented. The measurement was performed at the ISOLDE, CERN where delayed charged particles and γ rays were detected. The observed delayed γ rays are in agreement with the previously reported characteristics γ rays of ¹¹⁵Xe. Based on the experimental observations, the tentative ground-state spin of ¹¹⁵Cs is suggested to be 7/2⁺ or 9/2⁺. Furthermore, the measured decay branching ratio of delayed protons exceeds the previously reported value. Additionally, new delayed α-branching ratio and several reconstructed proton and α-unbound excited states of ¹¹⁵Xe are being reported for the first time. The properties of proton-unbound states at excitation energies from 3.9–7.9 MeV have been obtained by fitting the delayed proton spectrum via the Bayesian method. The measured lifetimes of these proton-unbound states are in the order of zeptoseconds.

• Author: P. Das; Ushasi Datta; S. Chakraborty; A. Rahaman; O. Tengblad; B. K. Agrawal; A. Becerril; J. Cederkall; J. Dey; A. Gottberg; Sk Md Adil Imam; M. Kowalska; J. Kurcewicz; M. Lund; S. Mandal; M. Madurga; N. Marginean; R. Marginean; C. Mihai; I. Marroquin; E. Nacher; A. Negret; S. Pascu; A. Perea; E. Rapisarda; F. Rotaru; J. Ray; P. Sharma; T. Stora; C. Sotty; V. Vedia; N. Warr; R. Wadsworth
• Department/s: Nuclear physics; Particle and nuclear physics
• Publishing year: 2023-12-01
• Language: English
• Publication/Series: Physical Review C
• Volume: 108
• Issue: 6
• Links: http://dx.doi.org/10.1103/PhysRevC.108.064304
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 2469-9985