Size distribution of the synthetic planets after undergoing one giant impact and photoevaporation. Left panel: maximum mass removed by the collision. Right panel: mean mass removed by the collision. Red: f_ice, f <  5%, green: 5%≤f_ice, f <  45%, blue: f_ice, f ≥ 45%, where f_ice, f is the final mass fraction of water relative to the total amount of heavy elements. Black lines: overall size distribution. Grey dotted lines: distribution without colissions (as in Fig. 4). Vertical dashed lines: peaks of the Kepler size distribution inferred by Fulton et al. (2017) (light violet) and Martinez et al. (2019) (dark violet).