Quadrupole moment and a proton halo structure in 17F (Iπ = 5/2+)

The quadrupole moment of light nuclei 17F in the ground state (Iπ = 5/2+) is measured by the β–NMR method. The effective charge of the last proton in a d5/2 orbit for 17F is extracted from the measured quadrupole moment Q(17F) divided by the quadrupole moment Qsp calculated with a single particle model. A proton effective charge of eeffp = 1.12 ± 0.07e is obtained, which is in agreement with that given by a particle–vibration coupling model calculation within the experimental error. The present value of the proton effective charge is strong evidence for the existence of a proton skin in 17F (Iπ = 5/2+).