In this work we concentrate on the evolution of the cluster population of the interacting galaxy M51 ( NGC 5194 ) , namely the timescale of cluster disruption and possible variations in the cluster formation rate .
We present a method to compare observed age vs. mass number density diagrams with predicted populations including various physical input parameters like the cluster initial mass function , cluster disruption , cluster formation rate and star bursts .
If we assume that the cluster formation rate increases at the moments of the encounters with NGC 5195 , we find an increase in the cluster formation rate of a factor of 3.0 ^ { +4.6 } _ { -1.2 } , combined with a disruption timescale which is slightly higher then when assuming a constant formation rate ( t _ { 4 } = \mbox { $ 2.0 ^ { +2.3 } _ { -1.1 } \times 10 ^ { 8 } $ } yr vs . 1.0 ^ { +0.6 } _ { -0.5 } \times 10 ^ { 8 } yr ) .
The measured cluster disruption time is a factor of 5 shorter than expected on theoretical grounds .
This implies that the disk of M51 is not a preferred location for survival of young globular clusters , since even clusters with masses of the order of 10 ^ { 6 } \mbox { $ \mbox { M } _ { \odot } $ } will be destroyed within a few Gyr .