Probing the Z=6 shell gap in 18C

We propose to study the Z=6 shell gap in neutron-rich carbon isotopes using ACTAR-TPC active target. The d(20O,3He)19N reaction will selectively populate the proton single-particle states in 19N. The aim of the experiment is to measure the spin-orbit splitting of 1p1/2 and 1p3/2 orbitals in 19N that will bring crucial information on the nature of spin-orbit interaction. In addition, the experiment will give us access to the cross-shell states in 19O through the neutron removal reaction d(20O,3H)19O that are important to benchmark modern shell model interactions.