Morphological decomposition of TNG50 galaxies: methodology and catalogue

ABSTRACT We present mordor (MORphological DecOmposeR), a new algorithm for structural decomposition of simulated galaxies based on stellar kinematics. The code measures the properties up to five components (a thin/cold and thick/warm disc, classical secular bulge, spherical halo), determines bar (if present). A comparison with other algorithms presented in literature yields overall good agreement, displaying higher flexibility correctly decomposing systems identifying bars crowded environments (e.g. ongoing fly-bys, often observable cosmological simulations). use analyse TNG50 simulation find following: (i) thick disc component undergoes strongest evolution binding energy-circularity plane, as expected when decrease their turbulent-rotational support cosmic time; (ii) smaller (with mass, $10^{9} \lesssim M_{*}/~\rm M_{\odot }\le 5 \times 10^{9}$) undergo major growth after z ∼ 1, whereas (iii) most massive ($5 10^{10} \lt 5\times 10^{11}$) evolve towards more spheroidal dominated objects down = 0 due frequent gravitational interactions satellites; (iv) fraction barred grows rapidly at high redshift stabilizes below 2, except that show occupation low redshift; (v) $M_{*} \sim 10^{11}~~\rm }$ exhibit highest relative occurrence 0, agreement observational studies. publicly release morphological catalogue galaxies.