Atomic masses of rare earth isotopes145Pm,145Sm and151Gd, derived from decay measurements of145Sm and151Gd

Abstract

The comparison of experimental with calculated K-capture probabilities yielded the decay energies of 145Sm and 151Gd, QEc=622(5) and 463(3)keV, respectively. Earlier discrepancies in the mass adjustment of these isotopes were removed and adjusted masses for 145Sm, 145pro and 151Gd derived. In the decay of ~5~Gd five new y-rays were found and the half-life remeasured to be 129(4) d.

Atomic masses of147m, 148m, 149m Tb,148Dy,150m, 152m Ho derived from decay properties

“…Details of the measurements and the data analysis are given in [18]. The 52Mn calibration at the end of the on-line measurements yielded E C/~ + =2.32 (10) in excellent agreement with the average value of the precision off-line experiment, EC/~ + =2.27(7) [18]. Comparison of the experimental positron fractions of r48mTb, ~5~…”

“…The result of a summation of all Q values within these two mass loops We have readjusted all mass differences given in Fig. 2 using a similar procedure as described earlier [6,10] Table 4 1983 Mass Evaluation of 149gTb excitation energy of 11/2-state, 36 keV Intensity ratio EC/~ + adjusted value see Table 4 Intensity ratio EC/fl + Table 4 differences are listed in Table 4. It should be emphasized that each of the readjusted masses is within 1.26 of the experimental input data.…”

“…In particular, the nuclei 147m'148m'149myb and as~ are connected by Q~c-and Q~-values to 144Sm, 145Sm, 14SEu, 146Gd and 147Gd. The masses of these nuclei are well known: 144Sm [9,35] is stable, the masses of 145Sm [10], 145Eu [5] and 147Gd [6] were redetermined in our earlier investigations, and accurate mass values for 146Gd were recently derived independently by reaction studies [11][12][13].…”

Precise atomic masses of147Eu,147Gd, and151Tb derived from their decay properties

“…Secondly, the ratio of K-capture probabilities, PK, for two transitions was measured and compared with the theoretical ratio. Again, since the theoretical is energy dependent, the QEC value can be derived [7][8][9]. In the decay studies of 147Eu and 147Gd both methods were applied and thus for each decay two independent results were obtained.…”

“…1, the masses of l'WEu, 147Gd and ~5~Tb are not only connected to stable A=147 and 151 masses by QEc values but are also interconnected by Q~ and (n,y) Q-values to 145Pm. Recently, the atomic masses of 145pm and of 151Gd were redetermined and earlier existing discrepancies in the adjustment of each of these masses were removed [7]. Consequently, the 14SPm and XSaGd masses can also offer an additional consistency test of the present mass measurements.…”