Picosecond lifetime measurements in 109Cd and 110Cd

166 S. Harissopulos et al. / Nuclear Physics A 683 (2001) 157–181
4. Results
4.1. The nucleus 110 Cd
For the data analysis in 110 Cd, the level scheme reported in [8,28] has been adopted. Part
of this level scheme, in which all the γ -transitions involved in our analysis are included,
isshowninFig.5.Theτ -curves obtained for the yrast band members in 110 Cd are shown
in Figs. 6 and 7. As shown in these Figs. the τ(x)-values of all levels investigated, do not
indicate any systematic errors: the data points τ(x) lie indeed, within statistical errors, on
a straight line. Due to statistics, these errors are, especially in the case of 4 + 1 and 6+ 1 states,
relatively large. The mean lifetimes τ displayed in parts (c) of these figures have been
deduced as the weighted average indicated by a straight line of the respective τ(x) values.
The results are summarized in Table 2.
The mean lifetime of the 2 + 1
state (τ = 8.7(12) ps) determined here, is statistically in
agreement with that reported by Piiparinen et al. (τ = 9.2(6) ps) in [28] as well as that
adopted in the most recent data compilation of A = 110 nuclei (τ = 7.78(10) ps) [29].
For the 4 + 1
state, the DDCM analysis of our data yielded a mean lifetime τ = 1.0(5) ps.
The corresponding value in [29] is τ = 1.05(13) ps. It has to be noticed that the mean
lifetimes adopted in [29] for the 2 + 1 and 4+ 1
levels have been derived in Coulomb excitation
measurements. Our result for the 4 + 1
state is further in agreement with that obtained
recently by Lobach et al. (τ = 1.18 +0.32
−0.18 ) [30]. This applies also for the 6+ 1
level for which
Fig. 5. Partial level scheme of 110 Cd (from Refs. [8,28]). The width of the arrows represents the
relative intensity measured in the present work for the corresponding transition (see also text). The
excitation energy of each of the three different 8 + states is given in parenthesis. The mean lifetimes
or mean lifetime limits determined in the present work are also displayed.