In many discharges at ASDEX Upgrade (AUG) fast particle losses can be observed due to Alfvénic gap modes, reversed shear Alfvén eigenmodes or core-localized beta Alfvén eigenmodes. For the first time, simulations of experimental conditions in the AUG fusion device are performed for different plasma equilibria (particularly for different, also non-monotonic q profiles). The numerical tool is the extended version of the HAGIS code (Pinches et al 1998 Comput. Phys. Commun. 111 133–49, Brüdgam 2010 PhD Thesis), which also computes the particle motion in the vacuum region between the vessel wall in addition to the internal plasma volume. For this work, a consistent fast particle distribution function was implemented to represent the strongly anisotropic fast particle population as generated by ICRH minority heating. Furthermore, HAGIS was extended to use more realistic eigenfunctions, calculated by the gyrokinetic eigenvalue solver LIGKA (Lauber et al 2007 J. Comput. Phys. 226 447–65). The main aim of these simulations is to allow fast ion loss measurements to be interpreted with a theoretical basis. Fast particle losses are modelled and directly compared with experimental measurements (García-Muñoz et al 2010 Phys. Rev. Lett. 104 185002). The phase space distribution and the mode-correlation signature of the fast particle losses allows them to be characterized as prompt, resonant or diffusive (non-resonant). The experimental findings are reproduced numerically. It is found that a large number of diffuse losses occur in the lower energy range (at around 1/3 of the birth energy) particularly in multiple mode scenarios (with different mode frequencies), due to a phase space overlap of resonances leading to a so-called domino (Berk et al 1995 Nucl. Fusion 35 1661) transport process. In inverted q profile equilibria, the combination of radially extended global modes and large particle orbits leads to losses with energies down to 1/10th of the birth energy.