Q&A: Galaxies, Galaxy Clusters, AGN, and Quasars
We really don't know. The best studied systems are sets
of 2 full galaxies which are violently colliding, such as the Antennae.
A Chandra image and discussion of the Antennae collision may
be found here:
In these strongly interacting systems there should be a large amount of
stellar formation, triggered by collisions between huge gas clouds.
However, in a system such as the Milky Way and the Magellanic Clouds
(Large or Small), the smaller galaxy gets torn apart by the tidal
forces from the larger galaxy (in this case the Milky Way). It is not
clear at the moment how much star formation activity is generated by
such a collision, it may be a negligible amount. This type of
collision is sometimes referred to as "galactic cannibalism."
So, the short answer is that the answer to your question is not known
at this time. You may be interested in our discussion of tidal forces
in the Universe, found in the following Chandra Chronicles article: