Magnetic moments of proton drip-line nuclei13O and9C

The magnetic moments of the proton drip-line nuclei13O(Iπ = 3/2−,T1/2 = 8.6 ms) and 9C(Iπ = 3/2−,T1/2 = 126 ms) have been determined for the first time through the combined techniques of polarized radioactive nuclear beams andβ-NMR detection. The observed magnetic moments are ¦μ(13O)¦ = 1.3891 ±0.0003μN and ¦μ(9C)¦ = 1.3914 ±0.0005μN. Spin expectation values 〈σ〉 are deduced to be 0.76 and 1.44 for13O and9C, respectively. While the 〈σ〉 of13O is consistent with the systematics from isospinT= 1/2 mirror pairs, the 〈σ〉 of9C is unusually large, even far larger than the single particle value, 〈σ〉 = 1.