Nuclear Spins of Neutron-deficient Promethium, Samarium, Europium and Gadolinium Isotopes

Abstract

Spin-measurements have been performed on some neutron-deficient promethium, samarium, europium and gadolinium isotopes using conventional atomic-beam magnetic resonance techniques. The results are: ¹⁴¹Pm (20.9 min) I=5/2, ¹⁴⁰Sm (14.8 min) I=0, ¹⁴¹Sm (11.3 min) I=1/2, ^141mSm (22.9 min) I=11/2, ¹⁴²Sm (72.5 min) I=0, ¹⁴³Sm (8.8 min) I=3/2, ¹⁴⁵Eu (5.93 d) I=5/2, ¹⁴⁶Eu (4.65 d) I=4, ¹⁴⁷Eu (22 d) I=5/2, ¹⁴⁸Eu (54 d) I=5, ¹⁴⁹Eu (93.1 d) I=5/2, ¹⁵⁰Eu (12.6 h) I=0, ¹⁴⁵Gd (22.9 min) I=1/2, ¹⁴⁷Gd (38.5 h) I=7/2, ¹⁴⁹Gd (9.4 d) I=7/2, ¹⁵¹Gd (120 d) I=7/2. The investigated nuclei appear close to the shell closure at neutron number N=82. A systematic review of the low-lying states of odd-even and doubly-odd nuclei in this region is presented.