We study the impact of local density and stellar mass on the structure and morphology of approximately 500 quiescent and star-forming galaxies from the VIMOS Spectroscopic Survey of a Superstructure in COSMOS ( VIS ^ { 3 } COS ) .
We perform bulge-to-disc decomposition of the surface brightness profiles and find \sim 41 \pm 3 % of > 10 ^ { 10 } \mathrm { M _ { \odot } } galaxies to be best fitted with two components .
We complement our analysis with non-parametric morphological measurements and qualitative visual classifications .
We find that both galaxy structure and morphology depend on stellar mass and environment for our sample as a whole .
We only find an impact of the environment on galaxy size for galaxies more massive than 10 ^ { 11 } \mathrm { M _ { \odot } } .
We find higher Sérsic indices ( n ) and bulge-to-total ratios ( B / T ) in high-density regions when compared to low-density counterparts at similar stellar masses .
We also find that galaxies with higher stellar mass have steeper light profiles ( high n , B / T ) compared to galaxies with lower stellar mass .
Using visual classifications , we find a morphology–density relation at z \sim 0.84 for galaxies more massive than 10 ^ { 10 } \mathrm { M _ { \odot } } , with elliptical galaxies being dominant at high-density regions and disc galaxies more common in low-density regions .
However , when splitting the sample into colour–colour-selected star-forming and quiescent sub-populations , there are no statistically significant differences between low- and high-density regions .
We find that quiescent galaxies are smaller , have higher Sérsic indices ( for single profiles , around n \sim 4 ) , and higher bulge-to-total light ratios ( for decomposed profiles , around B / T \sim 0.5 ) when compared to star-forming counterparts ( n \sim 1 and B / T \sim 0.3 , for single and double profiles , respectively ) .
We confirm these trends with non-parametric quantities , finding quiescent galaxies to be smoother ( lower asymmetry , lower M _ { 20 } ) and to have most of their light over smaller areas ( higher concentration and Gini coefficient ) than star-forming galaxies .
Overall , we find a stronger dependence of structure and morphology on stellar mass than on local density and these relations are strongly correlated with the quenching fraction .
The change in average structure or morphology corresponds to a change in the relative fractions of blue disc-like galaxies and red elliptical galaxies with stellar mass and environment .
We hypothesise that the processes responsible for the quenching of star formation must also affect the galaxy morphology on similar timescales .