From the Tully-Fisher relation to the fundamental plane through mergers

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 lambda cold dark matter cosmogony. Using a Sersic growth curve and an orthogonal fitting method, we find that the Fundamental Plane of our merger remnants is described by the relation R-e infinity sigma I-1.48+/-0.01(0)e(-0.75+/-0.01), which is in good agreement with that reported from the Sloan Digital Sky Survey, R-e infinity sigma I-1.49+/-0.05(0)e(-0.75+/-0.01). However, the R-1/4-profile leads to a Fundamental Plane given by R-e infinity sigma I-1.79+/-0.01(0)e(-0.60+/-0.01). In general, the correlation found in our merger remnants arises from homology breaking (V-2 infinity sigma(nu)(0), RgRe eta) in combination with a mass scaling relation between the total and luminous mass, M infinity M-L(gamma). Considering an orthogonal fitting method, it is found that 1.74 less than or similar to v less than or similar to 1.79, 0.21 less than or similar to eta less than or similar to 0.52 and 0.80 less than or similar to v less than or similar to 0.90 depending on the adopted profile (Sersic or R-1/4).