We present a high resolution study of the impact of realistic satellite galaxies , extracted from cosmological simulations of Milky Way haloes including 6 Aquarius suites and Via Lactea \ @ slowromancap ii @ , on the dynamics of the galactic disc .
The initial conditions for the multi-component Milky Way galaxy were generated using the GalIC code , to ensure a system in dynamical equilibrium state prior to addition of satellites .
Candidate subhaloes that came closer than 25 kpc to the centre of the host DM haloes with initial mass enclosed within the tidal radius , M _ { \textrm { tid } } \geq 10 ^ { 8 } M _ { \odot } = 0.003 M _ { \textrm { disc } } , were identified , inserted into our high resolution N-body simulations and evolved for 2 Gyr .
We quantified the vertical heating due to such impacts by measuring the disc thickness and squared vertical velocity dispersion \sigma _ { z } ^ { 2 } across the disc .
According to our analysis the strength of heating is strongly dependent on the high mass end of the subhalo distribution from cosmological simulations .
The mean increase of the vertical dispersion is \sim 20 km ^ { 2 } s ^ { -2 } Gyr ^ { -1 } for R > 4 kpc with a flat radial profile while , excluding Aq-F2 results , the mean heating is < 12 km ^ { 2 } s ^ { -2 } Gyr ^ { -1 } , corresponding to 28 % and 17 % of the observed vertical heating rate in the solar neighbourhood .
Taking into account the statistical dispersion around the mean we miss the observed heating rate by more than 3 \sigma .
We observed a general flaring of the disc height in the case of all 7 simulations in the outer disc .