Namangan Institute of Engineering and Technology
nammti.uz
10.25.2023
Pg.254
A theoretical analysis of the spectroscopic characteristics of the states of the positive parity
bands
158,160
Gd was carried out within the framework of a phenomenological model [1,2], which
takes into account the Coriolis mixing of the states of low-lying rotational bands.
The energy spectrum of positive parity levels and the reduced probabilities of E2- and M1-
transitions are calculated. The calculated values of the probability ratios of E2 transitions and the
multipole mixture coefficients δ(E2/M1) of
)
2
(
,
)
0
(
,
)
0
(
3
2
2
1
and
1
K
bands are
compared with the available experimental data [3-6], which provide satisfactory agreement.
Figure 1 shows the theoretical and experimental energies of
156
Gd levels.
Calculated and experimental [6] values of the multipole mixture coefficients δ(E2/M1) from
states of
0
,
,
1
K
bands for
158
Gd are given in Table 1.
It is shown that the effect of mixing of low-lying bands plays an important role and is
significantly manifested in the probabilities of electromagnetic transitions even at low spins.
0
1
2
3
4
5
6
7
8
9
15
3
E (MeV)
8
1
2
K
2
2
K
4
0
K
3
0
K
2
0
K
1
0
K
6
6
10
8
6
14
12
10
8
18
16
14
12
10
8
30
28
26
24
22
20
18
16
14
12
10
8
13
14
12
11
10
9
8
7
5
3
4
6
6
6
6
4
4
4
4
4
4
2
2
2
2
2
2
2
0
0
0
0
0
exp. theor
exp. theor
exp. theor
exp. theor
exp. theor
exp. theor
exp. theor
156
Gd
5
0
K
Pic. 1. Comparison of experimental and theoretical energy levels.
