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In many discharges at ASDEX Upgrade fast particle losses can be observed dueto Alfv\'enic gap modes, Reversed Shear Alfv\'en Eigenmodes or core-localizedBeta Alfv\'en Eigenmodes. For the first time, simulations of experimentalconditions in the ASDEX Upgrade fusion device are performed for differentplasma equilibria (particularly for different, also non-monotonic q profiles).The numerical tool is the extended version of the HAGIS code [Pinches'98,Br\"udgam PhD Thesis, 2010], which also computes the particle motion in thevacuum region between vessel wall in addition to the internal plasma volume.For this work, a consistent fast particle distribution function was implementedto represent the strongly anisotropic fast particle population as generated byICRH minority heating. Furthermore, HAGIS was extended to use more realisticeigenfunctions, calculated by the gyrokinetic eigenvalue solver LIGKA[Lauber'07]. The main aim of these simulations is to allow fast ion lossmeasurements to be interpreted with a theoretical basis. Fast particle lossesare modeled and directly compared with experimental measurements[Garc\'ia-Mu\~noz'10]. The phase space distribution and the mode-correlationsignature of the fast particle losses allows them to be characterized asprompt, resonant or diffusive (non-resonant). The experimental findings arereproduced numerically. It is found that a large number of diffuse losses occurin the lower energy range (at around 1/3 of the birth energy) particularly inmultiple mode scenarios (with different mode frequencies), due to a phase spaceoverlap of resonances leading to a so-called domino [Berk'95] transportprocess. In inverted q profile equilibria, the combination of radially extendedglobal modes and large particle orbits leads to losses with energies down to1/10th of the birth energy.

Multi-mode Alfv\'enic Fast Particle Transport and Losses: Numerical vs. Experimental Observation