Abstract
We investigate the growth of bar instability in stellar disks embedded in fully cosmological halos. We choose a Lambda -CDM cosmology (i.e. Omega_Λ() = 0.7, Omegam() = 0.3, H[0] = 70 km/s/Mpc) with 25h-1 Mpc of box size. The halo was selected from a low-resolution run (128^3 particles), it doesn't suffer major mergers since z = 5 and it lives in a low-density environment. Then we re-simulate the halo at 8 times higher resolution, following the whole simulation box with a multi-mass tecnique to account for the large-scale tidal forces. The stellar disk is embedded in the halo at a redshift z = 2. The evolution of the system spans more than 10 Gyr down to z = 0.