Yrast structures of neutron-rich $^{51}$Ca and $^{52}$Sc

An $N$=32 subshell closure in neutron-rich nuclei around doubly-magic $^{48}$Ca$^{ }$occurs due to the weakening of the strong $\pi $f$_{7/2 }$- $\nu $f$_{5/2}$ monopole interaction as protons are removed from the f$_{7/2}$ shell. With more proton removed, the splitting between the $\nu $p$_{1/2}$ and $\nu $f$_{5/2}$ states may be sufficient to produce a subshell closure at $N$=34. $\gamma \gamma $ coincidence events, from species produced in deep-inelastic collisions of a $^{48}$Ca beam on a thick $^{238}$U target, were collected with the Gammashere array at Argonne. The same system was investigated by employing the PRISMA spectrometer coupled with the CLARA $\gamma $-ray multi-detector array at the INFN, LNL Legnaro. Analysis of the combined data sets allowed us to identify the $\gamma $ transitions in $^{51}$Ca and $^{52}$Sc, and to construct extended level schemes. The energy of these states will be compared with the results of shell model calculations.