Investigation of very neutron deficient Ru and Rh nuclei with the help of (⁴⁰Ca;yp+zαγ) reactions

Abstract

⁴⁰Ca beams from the Munich tandem and from the Munich heavy ion postaccelerator have been used to produce very neutron deficient Ru and Rh nuclei with⁵⁸Ni (⁴⁰Ca,yp+zαγ) reactions. The nuclei⁹²Ru,⁹⁴Ru and⁹⁵Rh have been studied with in-beam γ ray spectroscopy consisting of the measurement of excitation functions, γ γ coincidences, γ ray angular distributions and life times with the recoil distance method. The following new level energies, spin parity values and half-lives have been deduced:⁹²Ru: 865.3 keV 2⁺; 1,855.8 (4⁺); 2,672.7 (6⁺); 2,834.6 (8⁺) 100±14 ns; 3,640.3 (10⁺), 4,206.1 (12⁺)⁹⁴Ru: 2,624.7 (5⁻) 530 ⁺⁵⁰⁰₋₂₀₀ ps; 3,991.7 (10⁺); 4,197.9 (9⁻); 4,489.3 (11⁻) 780±120 ps; 4,717.1 (12⁺) 35±3ps; 5,568.4 (13⁻); 5.826.8 (14⁻); 6,360.3 (14⁻); 6,614.7 (13⁺); 7,158.3 (14⁺); 7,774.1 (15); 8,412.1 (16); 9,042.2 (17)⁹⁵Rh: 1,350.7 (13/2⁺); 2,067.2 (17/2⁺); 2,236.2 (17/2⁻) 15±5ns; 2,449.0 (21/2⁺) 2.1±0.3 ns; 3,241.2 (21/2⁻); 3,724.1 (25/2⁺); 3.908.9 (25/2⁻); 4,307.2 (27/2⁺); 4,457.9; 4,716.9; 5,063.2; 6,797.3; 7,627.4 The residual activities have been studied with multi spectra analysis'. The decay scheme of⁹⁴Rh(25±2 s) has been established.