Systematic dependence of the slowing-down environment on nuclear lifetime measurements by the Doppler-shift attenuation method

Abstract

The mean life of the ${}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}$ 3.34 MeV level measured by Doppler-shift attenuation method at an average recoil velocity of $0.009c$, shows large fluctuations with different slowing-down materials ranging from Li to Pb. These fluctuations are correlated with a linear dependence of the "apparent" mean life $\tau$ on the electronic slowing-down time $\alpha$.