Absσa ct. In 야tis paper, we report on optic외ly detected adiabatic fast passage transients for the N-V center in type Ib diamond. The r얹띠tspro년de evidence for the triplet character eA) of the ground stateof theN-V center, and밍ve further insight intothe photo-잉netics ofthe N-Vcenter. In addition measurements of optically detected cross-relaxation, involving the spin sublevels of theN-Vcenter 3A ground state, arediscussed.