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Transition discs with evacuated inner cavities are expected to be a natural outcome of the interplay between X-ray driven photoevaporation (XPE) and giant planet formation. Massive planets can reduce the inflow of material from the outer to the inner disc, therefore triggering the earlier onset of disc dispersal due to photoevaporation through a process known as Planet Induced PhotoEvaporation (PIPE, Rosotti+ 2013). In this case, cavities are formed as material inside the planetary orbit is removed by photoevaporation, leaving only the outer disc to drive the migration of the giant planet. We investigate the impact of XPE on giant planet migration, and focus specifically on the case of transition discs with evacuated inner cavities inside the planet location. This is important to determine under what circumstances photoevaporation is efficient at halting the migration of giant planets, thus affecting the final orbital distribution of a population of planets. For this purpose, we use 2D FARGO simulations to model the migration of giant planets in a range of primordial and transition discs subject to XPE. The results are then compared to the migration tracks of planets obtained by the impulse approximation, which is commonly employed in 1D planet population synthesis approaches. The 2D FARGO simulations show that once the disc inside the planet location gets depleted of gas, planet migration ceases. This contradicts the results obtained by the impulse approximation in 1D, which predicts the strong, accelerated inward migration of planets in discs that have been cleared inside the planetary orbit. These results suggest that the impulse approximation may not be suitable to describe the migration of giant planets embedded in transition discs with inner cavities.

The imprint of X-ray photoevaporation on the orbital distribution of giant planets