System size scan of heavy flavor $R_{AA}$ and $v_n$ using PbPb, XeXe, ArAr, and OO collisions

Experimental measurements indicate no suppression (e.g. $R_{pPb} \sim 1$) but a surprisingly large D meson $v_2$ was measured in pPb collisions. In order to understand these results we use Trento+v-USPhydro+DAB-MOD to make predictions and propose a system size scan at the LHC involving $^{208}$PbPb, $^{129}$XeXe, $^{40}$ArAr, and $^{16}$OO collisions. Whatever the chosen transport model, we find that the nuclear modification factor approaches unity as the system size is decreased, but nonetheless, in the 0-10$\%$ most central collisions $v_2\{2\}$ is roughly equivalent regardless of system size. These results arise from a rather non-trivial interplay between the shrinking path length and the enhancement of eccentricities in smaller systems. Finally, we also find a surprising sensitivity of D mesons $v_2\{2\}$ in 0-10$\%$ centrality class at $p_T = 2-10 \,{\rm GeV}$ to the slight deformation of $^{129}$Xe recently found at LHC.