Fate of stellar bars in minor merger of galaxies
  Minor merger of galaxies are common during the evolutionary phase of
galaxies. Here, we investigate the dynamical impact of a minor merger (mass
ratio 1:10) event on the final fate of a stellar bar in the merger remnant. To
achieve that, we choose a set of minor merger models from the publicly
available GalMer library of galaxy merger simulations. The models differ in
terms of their orbital energy, orientation of the orbital spin vector, and
morphology of the satellite galaxy (discy/spheroidal). We demonstrate that the
central stellar bar, initially present in the host galaxy, undergoes a
transient bar amplification phase after each pericentre passage of the
satellite; in concordance with past studies of bar excitation due to tidal
encounter. However, once the merger happens, the central stellar bar weakens
substantially in the post-merger remnants. The accumulation of satellite's
stars in the central region of merger remnant plays a key role in the bar
weakening process; causing a net increase in the central mass concentration as
well as in the specific angular momentum content. We find that the efficiency
of mass accumulation from the satellite in the central parts of merger remnants
depends on the orbital parameters as well as on the satellite's morphology.
Consequently, different minor merger models display different degrees of bar
weakening event. This demonstrates that minor merger of galaxies is a plausible
avenue for bar weakening in disc galaxies.
