Evidence of antimagnetic rotation in an odd-odd nucleus: The case of 142Eu

Abstract

The present work reported a conclusive evidence for anti-magnetic rotational (AMR) band in an odd-odd nucleus 142 Eu. Parity of the states of a quadrupole sequence in 142 Eu was firmly identified from polarization measurements using the Indian National Gamma Array and lifetimes of some of the states in the same structure were measured using the Doppler shift attenuation method. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J (2) /B(E2) values conclusively established the origin of these states as arising from Antimagnetic rotation. The results were well reproduced by numerical calculations within the framework of a semi-classical geometric model.

Theoretical investigation of the antimagnetic rotation in 104Pd *

“…1 (a). This indicates that the AMR band observed in 104 Pd will be terminated around this rotational frequency and a four quasiparticle band will appear, which is similar to that observed in 143 Eu [13].…”

“…106 Cd [4], 107 Cd [5], 108 Cd [6,7], 110 Cd [8], 101 Pd [9][10][11], and 104 Pd [12]. Recently, possible AMR bands have also been reported in Eu (Z = 63) isotopes, including 143 Eu [13] and 142 Eu [14]. The existence of AMR still needs further investigation in 109 Cd [15], 100 Pd [16], 144 Dy [17] and 112 In [18] with lifetime measurements.…”

Systematic study of magnetic and antimagnetic rotational bands

“…Up to now, 253 magnetic rotational bands in 123 nuclei have been reported in the A ∼ 60 [18,19,[37][38][39][40][41][42], 80 [16,, 110 [26,30,, 140 [13,17,, and 190 [6,7,20,35, mass regions. In contrast, the experimental observation of AMR bands is scarce and so far only 40 antimagnetic rotational bands are reported in 29 nuclei and mainly distributed in the A ∼ 60 [19,42,278], 110 [21, 23-26, 29-31, 40, 110, 112, 115, 119, 130, 279-313], and 140 [156,215,[314][315][316][317][318] In order to promote the study of magnetic and antimagnetic rotations, the systematics of MR and AMR bands are required. In this paper, we mainly focus on the discussion of spin I, kinematic moment-of-inertia  (1) = I/ω, and dynamic moment-of-inertia  ( 2 ) versus rotational frequency ω, as well as energy staggering parameter S(I), the magnetic dipole reduced transition probability B(M1), the electric quadrupole reduced transition probability B(E2) and the B(M1)/B(E2) ratio versus spin I in the A ∼ 60, 80, 110, 140, and 190 mass regions for MR bands.…”

Possible antimagnetic rotation bands in $^{100}$Pd: a particle-number conserving investigation

“…According to the lifetime measurement, AMR bands with different configurations have been observed mainly in the weakly deformed Cd (Z = 48) and Pd (Z = 46) isotopes in the A ≈ 100 mass region, including [105][106][107][108]110 Cd [3][4][5][6][7][8] and 101,104 Pd [9][10][11][12]. In addition, several possible AMR bands have been observed in 109 Cd [13], 112 In [14], 144 Dy [15], and 142,143 Eu [16,17], which need further confirmation by lifetime measurements.…”