A new result of investigations of the hyperfine structure (hfs) anomaly in Be isotopes is presented. The hfs constant for ${}^{11}\mathrm{Be}$ is obtained by using the core plus neutron type wave function$\hspace{1em}|{2s}_{1/2}〉+|{1d}_{5/2}\times 2^{+};{\frac{1}{2}}^{+}〉.$ A large hfs anomaly of ${}^{11}\mathrm{Be}$ is found, which is mainly due to the large radius of the halo single-particle state.

• Received 10 September 1998

DOI:https://doi.org/10.1103/PhysRevC.59.210