Levels in152Gd and152Sm populated by the decay of152Eu

Abstract

The energy level schemes of 152Gd and 152Sm have been established on the basis of singles ?-spectra, and ?-? coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC//~ + and /3-decays of 152Eu to 152Sm and 152Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and log ft values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model.

On the newly proposed levels in152Gd and152Sm

“…The energies, relative intensity and shapes of these two peaks support this explanation. We therefore conclude that the new y-rays reported in [3] are not emitted in the decay of t52Eu (13y) and that there is no evidence for the existence of the five new levels claimed in [3] to be populated in the decay of ~52Eu (13 y). A level at 1314.7 keV with J" = 1 -in tS2Gd has been observed in the decays of ~52'"Eu (0-, 9.3 h) [1] and ~S2Tb (2-, 17.5 h) [1], the 1314.7 keV y-ray being the strongest deexciting y-ray of this level.…”

“…1 and Table 1 one can see that all the neighbouring y-rays listed in Table 1 appear in Fig. 1 with prominent peaks while the new y-rays (except 166.91 keV) of [3] are not present. For the 166.91 keV y-ray the present study suggested that this line together with the 161.2 keV peak (Fig.…”

“…Since the measurements of Meyer [2] several studies on the decay of I52Eu have been published as compiled in [1 ], but no new levels were reported until the recent work of Steward et al [3], where three new levels in lS2Gd and two new levels in lS2Sn] were proposed on the basis of y singles and y -y coincidence spectra. Obviously, the intensities of these new y-rays are not sufficient for obtaining reliable y -y coincidence data which are essential for establishing new levels.…”

N=90region: The decays ofEu152Kulp1, Wood2, Allmond3 et al. 2007Phys. Rev. C420230View full textAdd to dashboardCite

“…(14) 0.0814 (27) 6 + 706.9 316.08 (17) 0.038 (9) 4 + 366.5 656.51 (14) 0.549 (18) 2 + 121.8 901.34 (15) 0.328 (13) 1041.11 (14) 3 − 2.00 (9)/2.25 (7) 4 + 366.5 674.64 (14) 0.656 (21) 2 + 121.8 919.41 (14) 1.59 (5) 1082. 43 (15) 0.077 (4) 4 + 1023.0 210.95 (14) 0.0143 (6) 5 2 + 810.5 423.40 (14) 0.0112 ( (23) 0.0043 (9) 5 0 + 1082.9 209.84 (14) 0.0241 (10) 5 3 − 1041.1 251.65 (14) 0.247 (9) 4 + 1023.0 269.75 (14) 0.0285 (25) 1 − 963.4 329.43 (14) 0.446 (15) 2 + 810.5 482.35 (14) 0.093 (3) 0 + 684.7 608.06 (15) 0.0010 (3) 5 4 + 366.5 926.32 (14) 0.99 (3) 2 + 121.8 1171.20 (20) 0.141 (7) (22) 0.0028 (5) 5 5 − 1221.5 150.20 (14) 0.00370 (24) 5 2 + 1085.9 285.98 (18) 0.037 (6) 3 − 1041.1 330.67 (14) 0.0377 (19) 4 + 1023.0 348.86 (16) 0.0052 (8) 5 2 + 810.5 561.26 (17) 0.0058 (5) 6 + 706.9 664.57 (20) 0.0373 (19) 4 + 366.5 1005.24 (15) 2.38 (8) 2 + 121.8 1249.95 (14) 0.713 (24) 1529.77 (14) 2 − no γ in/94 (4) 2 + 1292.8 237.02 (14) 0.0245 (13) 5 3 + 1233.9 295.99 (14) 1.64 (7) 2 + 1085.9 444.02 (14) 11.0 (4) 3 − 1041.1 488.74 (14) 1.59 (7) 1 − 963.4 566.41 (14) 0.514 (17) 2 + 810.5 719.36 (14) 0.357 (12) 2 + 121.8 1408.04 (14) 78.5 (26) 1579.39 (...…”

“…The adopted [12] intensity and the recently reevaluated [18] intensity for the 126 keV line are both based on just two measurements, I γ (126) = 0.045 (7) [25] and 0.091 (10) [26]. These two measurements were singles measurements and necessitated the resolution of the 126 keV line from the 122 keV line which is ∼1800 times stronger.…”