Specific features and symmetries for magnetic and chiral bands in nuclei

Abstract

Magnetic and chiral bands have been a hot subject for more than twenty years. Therefore, quite large volumes of experimental data as well as theoretical descriptions have been accumulated. Although some of the formalisms are not so easy to handle, the results agree impressively well with the data. The objective of this paper is to review the actual status of both experimental and theoretical investigations. Aiming at making this material accessible to a large variety of readers, including young students and researchers, I gave some details on the schematic models which are able to unveil the main features of chirality in nuclei. Also, since most formalisms use a rigid triaxial rotor for the nuclear system's core, I devoted some space to the semi-classical description of the rigid triaxial as well as of the tilted triaxial rotor. In order to answer the question whether the chiral phenomenon is spread over the whole nuclear chart and whether it is specific only to a certain type of nuclei, odd-odd, odd-even or even-even, the current results in the mass regions of $A\sim 60,80,100,130,180,200$ are briefly described for all kinds of odd/even-odd/even systems. The chiral geometry is a sufficient condition for a system of proton-particle, neutron-hole and a triaxial rotor to have the electromagnetic properties of chiral bands. In order to prove that such geometry is not unique for generating magnetic bands with chiral features, I presented a mechanism for a new type of chiral bands. One tries to underline the fact that this rapidly developing field is very successful in pushing forward nuclear structure studies.Comment: 80 pages, 22 figure

Chirality of Nd135 reexamined: Evidence for multiple chiral doublet bands

“…Recent reviews of both the experimental and theoretical investigation of the chiral bands can be found in Refs. [3][4][5][6][7]. The first chiral bands were observed in odd-odd nuclei at low spins, where the shape can be γsoft and the competition with other collective modes is important.…”

New candidate chiral nucleus in the A≈80 mass region: Br473582

“…To date, the chiral doublet bands, including Mχ D bands, have been reported in more than 40 nuclei in the A ≈ 80 [9,10], 100 [11][12][13][14][15][16][17][18], 130 [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35], and 190 [36][37][38][39][40][41][42] mass regions. For details, see recent reviews [43][44][45][46][47][48][49] or data tables [50].…”

Reexamining nuclear chiral geometry from the orientation of the angular momentum

“…For recent reviews, see Refs. [2][3][4][5][6][7][8]. With the prediction [9] and confirmation [10] of multiple chiral doublets (Mχ D) in a single nucleus, the investigation of chirality continues to be one of the hottest topics in nuclear physics [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29].…”