From the Tully–Fisher relation to the Fundamental Plane through mergers

Abstract

Abstract We set up a series of self-consistent N-body simulations to investigate the Fundamental Plane of merger remnants of spiral galaxies. These last ones are obtained from a theoretical Tully–Fisher relation at z = 1, assuming a constant mass-to-light ratio within the Λ cold dark matter cosmogony. Using a Sérsic growth curve and an orthogonal fitting method, we find that the Fundamental Plane of our merger remnants is described by the relation Reασ1.48±0.010I−0.75±0.01e, which is in good agreement with that reported from the Sloan Digital Sky Survey, Reασ1.49±0.050I−0.75±0.01e. However, the R1/4-profile leads to a Fundamental Plane given by Reασ1.79±0.010I−0.60±0.01e. In general, the correlation found in our merger remnants arises from homology breaking (V2ασν0, RgαRηe) in combination with a mass scaling relation between the total and luminous mass, MαMγL. Considering an orthogonal fitting method, it is found that 1.74 ≲ ν ≲ 1.79, 0.21 ≲ η ≲ 0.52 and 0.80 ≲ γ ≲ 0.90 depending on the adopted profile (Sérsic or R1/4).