of the early disc accretion scenario.

A similar scenario has been studied before by @moeckel09, M09 hereafter. They performed smoothed particle hydrodynamics simulations of a protoplanetary disc that is embedded in a flow of interstellar medium (ISM) with a velocity of $3\,\mathrm{km\, s^{-1}}$. They found that the mean accretion rate onto the star equals the rate expected from Bondi-Hoyle theory, whether a disc is present or not. We note that for the parameters they assumed, the theoretical Bondi-Hoyle radius is almost twice the radius of the disc. Here we follow up on the work by M09 by simulating the accretion process onto a protoplanetary disc for the typical conditions expected in a GC environment. We directly compare the outcome of two different smoothed particle hydrodynamics codes for the same set of initial conditions and different particle resolutions. We first discuss both the physical and numerical effects in our reference model and subsequently we compare the results of the different codes and particle numbers.

Expected physical effects
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In dense stellar systems, where both the velocity dispersion and the possibility of close stellar encounters are high, we expect the following physical effects to play an important role in the process of 