Cover Story (Issue 3, 2024) | First measurement of the ground-state mass of 22Al helpsto evaluate the ab-initio theory
Author: Prof. BaohuaSun (Beihang University)
How the strong interaction binds the ingredients (proton and neutron) of atomic nuclei, is the central quest of nuclear physics. Nuclear physicists have been addressing this question with different experimental techniques and theoretical approaches. Among them, the mass or binding energy of a nucleus, reflecting the interplay of all forces at work within the nucleus, has played a key role in the journey of understanding the nucleus and testing the theories.
In a recent study [1] published by the group in Lanzhou, the ground-state mass of 22Al, the known lightest bound Al isotope, has been measured for the first time with a precision of 10 keV. Such high precision was achieved by using the newly developed Bρ-defined IMS technique at CSRe. With the new mass, they determined the mirror energy differences (MEDs) of the 11,2 states in 22Al and 22F, the so-called mirror partners, with the uncertainty of about 50 keV. This precise value allows a crucial test of the state-of-the-art ab-initio calculations in an odd-odd mirror pair. They concluded that the substantial occupation of s1/2 orbit is vital in understanding the significant isospin symmetry breaking, and supports the suggested halo structure in the 1+1 state of 22Al.
References
[1] M.Z. Sun et al., Chinese Physics C 48 034002(2024)
