  Photo-heating associated with reionisation and kinetic feedback from
core-collapse supernovae have previously been shown to suppress the
high-redshift cosmic star formation rate. Here we investigate the interplay
between photo-heating and supernova feedback using a set of cosmological,
smoothed particle hydrodynamics simulations. We show that photo-heating and
supernova feedback mutually amplify each other's ability to suppress the star
formation rate. Our results demonstrate the importance of the simultaneous,
non-independent inclusion of these two processes in models of galaxy formation
to estimate the strength of the total negative feedback they exert. They may
therefore be of particular relevance to semi-analytic models in which the
effects of photo-heating and supernova feedback are implicitly assumed to act
independently of each other.
