Abstract

ACEVES, H.  and  VELAZQUEZ, H.. Scalings between physical and their observationally related quantities of merger remnants. Rev. mex. astron. astrofis [online]. 2005, vol.41, n.2, pp.523-532. ISSN 0185-1101.

We present scaling relations between the virial velocity (V) and the one-dimensional central velocity dispersion (σ₀); the gravitational radius (R_v) and the effective radius (R_e); and the total mass (M) and the luminous mass (M_L) found in N-body simulations of binary mergers of spiral galaxies. These scalings are of the form V² α₀^σ, R_v α R_e^β y M α M_L^γ. The particlar values obtained for {α,β,γ} depend on the method of fitting used [ordinary least-squares (OLS) or orthogonal distance regression (ODR)], the assumed profile [de Vaucouleurs (deV) or Sérsic (S)], and the size of the radial interval where the fit is done. The α and γ indexes turn out more sensitive to the fitting procedure, resulting for the OLS in a mean (α)_ols = 1.51 and (γ)_ols = 0.69, while for the ODR (α)_odr = 2.35 and (γ)_odr = 0.76. The β index depends more on the adopted type of profile, with (β)_deV = 0.13 and (β)s = 0.27. We conclude that dissipationless formed remnants of mergers have a strong breaking of structural and kinematical homology.

Keywords : Galaxies [Kinematics and dynamics]; Methods [Numerical]; N-body simulations.