Z = 50 core stability in 110Sn from magnetic-moment and lifetime measurements

Background: The structure of the semimagic 50Sn isotopes were previously studied via measurements of
B(E2; 21
+ → 01
+) and g factors of 21
+ states. The values of the B(E2; 21
+) in the isotopes below midshell at
N = 66 show an enhancement in collectivity, contrary to predictions from shell-model calculations.
Purpose: This work presents the first measurement of the 21
+ and 41
+ states’ magnetic moments in the unstable
neutron-deficient 110Sn. The g factors provide complementary structure information to the interpretation of the
observed B(E2) values.
Methods: The 110Sn nuclei have been produced in inverse kinematics in an α-particle transfer reaction from
12C to 106Cd projectiles at 390, 400, and 410 MeV. The g factors have been measured with the transient field
technique. Lifetimes have been determined from line shapes using the Doppler-shift attenuation method.
Results: The g factors of the 21
+ and 41
+ states in 110Sn are g(21
+) = +0.29(11) and g(41
+) = +0.05(14),
respectively. In addition, the g(41
+) = +0.27(6) in 106Cd has been measured for the first time. A line-shape
analysis yielded τ (110Sn;21
+) = 0.81(10) ps and a lifetime of τ (110Sn;31
−) = 0.25(5) ps was calculated from the
fully Doppler-shifted γ line.
Conclusions: No evidence has been found in 110Sn that would require excitation of protons from the closed
Z = 50 core.