The first candidate for chiral nuclei in the A∼80 mass region: 80Br

Evidence for Octupole Correlations in Multiple Chiral Doublet Bands

“…Such chiral doublet bands were first observed in N ¼ 75 isotones [2]. So far, more than 30 experimental candidates have been reported in the A ∼ 80, 100, 130, and 190 mass regions [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].Based on constrained triaxial covariant density functional theory (CDFT) calculations, it has been suggested that multiple chiral doublet (MχD) bands can exist in a single nucleus [21][22][23][24][25][26]. The theoretical prediction of MχD bands stimulated lots of experimental efforts [27][28][29][30][31].…”

“…The first experimental evidence for MχD bands was reported in 133 Ce [27], which confirmed the manifestation of triaxial shape coexistence in this nucleus. Later, Kuti et al reported a novel type of MχD bands with the same configuration in 103 Rh [29], which showed that chiral geometry can be robust against the increase of the intrinsic excitation energy.Compared to the A ∼ 130 and 100 mass regions, the A ∼ 80 mass region is a relatively new and less studied territory for the investigation of chiral symmetry breaking in rotating nuclei, with only one report of chiral doublet bands based on the πg 9=2 ⊗ νg 9=2 configuration in odd-odd 80 Br [18]. In 78 Br, the πg 9=2 ⊗ νg 9=2 band was suggested to have an obvious triaxial shape [32], which is suitable for the construction of chiral doublet bands.…”

“…Such chiral doublet bands were first observed in N ¼ 75 isotones [2]. So far, more than 30 experimental candidates have been reported in the A ∼ 80, 100, 130, and 190 mass regions [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].…”

“…Compared to the A ∼ 130 and 100 mass regions, the A ∼ 80 mass region is a relatively new and less studied territory for the investigation of chiral symmetry breaking in rotating nuclei, with only one report of chiral doublet bands based on the πg 9=2 ⊗ νg 9=2 configuration in odd-odd 80 Br [18]. In 78 Br, the πg 9=2 ⊗ νg 9=2 band was suggested to have an obvious triaxial shape [32], which is suitable for the construction of chiral doublet bands.…”

Lifetime measurements in mass regions A=100 and A=130 as a test for chirality in nuclear systems

“…Since the chiral symmetry is dichotomic, its spontaneous breaking by the axial angular momentum vector leads to a pair of degenerate ΔI = 1 rotational bands, called chiral doublet bands. Pairs of bands, presumably due to the breaking of the chiral symmetry in triaxial nuclei, have been found in the mass regions A∼130 [4][5][6][7][8][9], A∼105 [10][11][12][13][14][15] and A∼195 [16][17][18], and A∼80 [19]. There is also a significant interest from theoretical point of view to investigate the chiral phenomenon [2,[20][21][22][23][24].…”