Halo Nature of ^14,15C

We have used spectroscopic factors extracted from the (d,p) transfer reactions to calculate asymptotic normalization coefficients and root-mean-square (rms) radii for the valence neutron in ^14,15C. The obtained rms radii are 4.57±0.30, 5.78±0.36 and 5.82±0.60 fm for the first 1^-, 0^- excited states of ¹⁴C and the ground state of ¹⁵C, which are 1.84, 2.33 and 2.32 times larger than the size of their cores, repectively. These large values imply that ¹⁵C as well as ¹⁴C in its first 1^-, 0^- states are halo nuclei.