Proposeds=±1octupole bands inXe140

Abstract

Level structures of neutron-rich 140 Xe nucleus have been reinvestigated by using a triple γ coincidence study from the spontaneous fission of 252 Cf. Several new levels and transitions are identified. The previously observed s = +1 octupole band structure is confirmed and expanded. Another set of the △I = 2 positive-and negative-parity bands connected by strong E1 transitions is proposed as the s = −1 octupole band structure. Thus, the s = ±1 doublet octupole bands are completed in 140 Xe. The experimental B(E1)/B(E2) branching ratios indicate that the octupole correlations in 140 Xe are weak. The other characteristics of the s = ±1 octupole bands have been discussed.

Various nuclear structures in Xe140 studied by β decay of ground and isomeric states in I140Yagi1, Odahara2, Nıshıbata3 et al. 2022Phys. Rev. C2000View full textAdd to dashboardCite

“…The T 1/2 of the β decays of the g.s., the LSI, and the HSI are determined to be 0.38 (2), 0.91 (5), and 0.47(4) s, respectively. [5,11] are newly assigned to ones associated with the β decay of 140 I. Spin and parity (I π ) are taken from Ref.…”

“…The reported g factor of the 2 + state obtained by the correlation attenuation in randomly oriented magnetic fields in the spontaneous fission experiment of 252 Cf [13] was reproduced by theoretical calculations on an IBM-2 model, indicating vibrational collectivity. The octupole band in 140 Xe was found in the β decay of 140 I [16] and was investigated in detail in the experiments of spontaneous fissions of 248 Cm [4,5] and 252 Cf [11]. The γ band (I π = 3 + , 5 + , and 7 + at 1305-, 1573-, and 1955-keV levels, respectively) in 140 Xe was reported in the experiment of spontaneous fission of 248 Cm [5].…”

“…The level structure of this 140 Xe nucleus was reported in studies for experiments of spontaneous fission of 248 Cm [3][4][5] and 252 Cf [6][7][8][9][10][11][12][13] as well as thermal neutron-induced fission of 235 U [14,15] and 241 Pu [15]. Low-lying states were studied by β decay of 140 I to 140 Xe at the OSIRIS ISOL facility and a partial decay scheme was reported [16].…”

“…However, Ref. [11] proposed the existence of s = ±1 parity-doublet octupole bands and assignment of this positive-parity band as the s = −1 octupole band. Reference [12] supported the interpretation of the γ band by additional new data for 140 Xe and by systematic study of the γ bands in N = 86 isotopes of 142 Ba and 144 Ce.…”

Exploring the structure of Xe isotopes in A ~ 130 region: Single particle and collective excitations

“…131 Xe(Z = 54, N = 77) is one of the suitable candidate to study various band structures and interesting features of the nuclear shape in A ∼ 130. Only one qp (νh 11/2 ) band structure in 131 Xe is known [1,2], whereas, high spin band structures in 125 Xe [3] and triaxial bands in 129 Xe [4] have been reported. Availability of highj h 11/2 orbital for both proton particles and neutron holes makes 131 Xe also a suitable candidate to exhibit Magnetic Rotation (MR) at high spin.…”