Electric dipole moment of C 13

We calculate for the first time the electric dipole moment (EDM) of C13 generated by the isovector charge conjugation-parity (CP)-odd pion exchange nuclear force in the α-cluster model, which describes well the structures of low-lying states of the C13 nucleus. The linear dependence of the EDM of C13 on the neutron EDM and the isovector CP-odd nuclear coupling is found to be dC13=-0.33dn-0.0020G;π(1). The linear enhancement factor of the CP-odd nuclear coupling is smaller than that of the deuteron, due to the difference of the structure between the 1/21- state and the opposite-parity (1/2+) states. We clarify the role of the structure played in the enhancement of the EDM. This result provides good guiding principles to search for other nuclei with large enhancement factor. We also mention the role of the EDM of C13 in determining the new physics beyond the standard model.