In previous work, we studied the merger timescale of galaxies in a high-resolution cosmological hydro/N-bodysimulation. We now investigate the potential influence ofuncertainties in the numerical implementation of baryonic physics onthe merger timescale. The simulation used in the previous work wasaffected by the overcooling problem, which caused the central galaxiesof large halos to be too massive. This might be responsible forproducing a shorter merger timescale than that in the real universe. Weperform a similar simulation, but in which the stellar mass is reducedsignificantly to model another extreme case of low stellar mass. Ourresult indicates that in this case the merger timescale issystematically higher than that we measured before. However, thedifference in these two cases is only about ,except for satellites in nearly radial orbits where the difference islarger, reaching 23 percent. Since the two simulations correspond toboth the low and high stellar mass limiting cases, and nearly radialorbits account for only a small part of the satellites' orbits, ourresults indicate that the fitting formula that we presented previouslyis applicable to good accuracy.Key words: galaxies: clusters: general - galaxies: kinematics and dynamics - methods: numerical
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