The g-factor measurement as an ultimate test for nuclear chirality

Abstract

We present results of a series of experiments aimed at finding the most direct fingerprints of a phenomenon of nuclear chirality. These experiments brought a detailed knowledge of the so called partner bands in ¹³²La, ¹²⁸Cs and ¹²⁶Cs including absolute values of E2 and M1 transition probabilities obtained through the DSA (Doppler Shift Attenuation) method. Considering the indirect character of observables such as energies and transition rates we proposed measurement of the g-factor of a chosen state as a direct, ultimate test of chirality. Our experiment on the bandhead of partner bands in ¹²⁸Cs showed feasibility of this approach. Measured value of the g-factor which suggests non-chiral character of this state leads to another puzzle in the chirality studies — how the chirality emerges with increasing spin of levels along a partner band.

Graphical abstract

Keywords

nuclear chirality / electromagnetic transitions / electromagnetic moments / level lifetimes

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Declarations

The authors declare that they have no competing interests and there are no conflicts.

Acknowledgements

We want to express our deep gratitude to our late colleagues, Alexandr A. Pasternak and Tomasz Morek, for a long-standing collaboration and a significant contribution to our studies of nuclear chirality. In particular, to Alexandr A. Pasternak for playing a leading role in DSAM analysis and creating excellent software and to Tomasz Morek for a very important role in all stages of experiments and data analysis.

RIGHTS & PERMISSIONS

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