Hyperfine Structure Constant of the Neutron Halo Nucleus 11Be+
A. Takamine, M. Wada, K. Okada, T. Sonoda, P. Schury, T. Nakamura, Y. Kanai, T. Kubo, I. Katayama, S. Ohtani, H. Wollnik, and H. A. Schuessler Phys. Rev. Lett. 112, 162502 (2014)
Paper can be found here: https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.112.162502