Picosecond lifetime measurements in 109Cd and 110Cd

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Table 2 —continued Level I SF τ (ps) J π i → J π f E γ I i→f b i→f B(E2) [W u] E x (keV) (%) this work others a (keV) (arb. units) (%) this work others a 4172 23.1(38) 11.4(6) 12.0(6) c 12 + 1 → 10+ 1 561 44.9(11) 100 41(2) 39(2) c 5026 < 4 2.0(2) c 14 + 1 → 12+ 1 854 34.5(12) 100 > 14 29(3) c 4078 < 5 1.0(3) c 10 + 2 → 8+ 2 802 10.0(5) 100 > 16 74(24) c 1.2 +0.5 −0.3 d 60.4(186) d 4889 2.0(2) c 12 + 2 → 10+ 2 811 10(3) 37(2) c 2540 0.90 +0.40 −0.25 d 5 − → 4 + 998 13.9(6) 2879 < 1250 750(40) e 7 − → 6 + 399 22.1(5) 866(144) f → 5 − 339 11(1) g > 1.2 2.3(3) e 1.6(3) f 3346 71(4) c 9 − → 7 − 467 14.3(10) g 15.1(9) c a A recent data compilation can be found in Ref. [29]. b From Ref. [29]. c From Ref. [28]. d From Ref. [30]. e According to [30], after a reanalysis of the data of Ref. [28]. f From Ref. [32]. g Estimated value since doublet γ -line. h B(E2) value calculated using the mean lifetime given in [29]. 168 S. Harissopulos et al. / Nuclear Physics A 683 (2001) 157–181
S. Harissopulos et al. / Nuclear Physics A 683 (2001) 157–181 169 Fig. 6. DDCM analysis of the three lowest yrast states of 110 Cd. For a given level, the respective data in (a) correspond to the numerator of Eq. (6), i.e. the time distribution of the “difference” between the depopulation and the population of the level in consideration. Data in (b) correspond to the denominator of Eq. (6) multiplied by −1, i.e. the opposite values of the first time derivative of the respective decay curve. By dividing data points shown in a) by the corresponding data points shown in (b) one obtains the τ(x) values shown in (c). The solid straight lines shown in parts (c) correspond to the displayed mean lifetimes τ . These have been obtained by averaging the respective τ(x) values. our analysis yielded a mean lifetimes of 0.9(5) ps, whereas Lobach et al. have derived τ = 0.58 +0.22 −0.13 [30]. For the 8+ 2 state a mean lifetime of 1.5(5) ps has been here determined. For this level, a τ = 0.9(3) ps has been adopted in the compilation of De Frenne and Jacobs [29]. At this point it has to be mentioned that the presence of the 164 keV γ -ray, which according to [28] depopulates the 8 + level at E x = 3440 keV excitation energy and feeds the 8 + 2 state at E x = 3275 keV, was not present in our γ -singles spectra. Hence, no such feeder was taken into account in the analysis of the latter state. Furthermore, in accordance to [28], a 707 keV γ -ray depopulates an 8 + state at E x = 3187 keV and feeds the 6 + 1 level. In the γ -singles spectra taken here, this γ -transition is a member of a multiplet of γ -lines, so that no decay curve could be obtained. Hence, it was not possible to consider the 707 keV γ -transition in the analysis of the 6 + 1 level. From the intensity balance of this state however (see Table 2), it can be seen that the intensity of the 707 keV γ -ray relative to this of the 938 keV γ -transition (6 + 1 → 4+ 1 ) is less than 2.2%. Hence, the mean lifetime determined for the 6 + 1 state is rather weakly dependent on the decay time of the 8+ 1 level
Page 1 and 2: Nuclear Physics A 683 (2001) 157-18
Page 3 and 4: S. Harissopulos et al. / Nuclear Ph
Page 7 and 8: Fig. 3. Experimental decay curves Q
Page 11: Table 2 Mean lifetimes τ and B(E2)
Page 25: S. Harissopulos et al. / Nuclear Ph

Picosecond lifetime measurements in 109Cd and 110Cd

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