Mass Evaporation Rate of Globular Clusters in a Strong Tidal Field
  The mass evaporation rate of globular clusters evolving in a strong Galactic
tidal field is derived through the analysis of large, multi-mass $N$-body
simulations. For comparison, we also study the same evaporation rates using
MOCCA Monte Carlo models for globular cluster evolution. Our results show that
the mass evaporation rate is a dynamical value; that is, far from a constant
single number found in earlier analytical work and commonly used in the
literature. Moreover, the evaporation rate derived with these simulations is
higher than values previously published. These models also show that the value
of the mass evaporation rate depends on the strength of the tidal field. We
give an analytical estimate of the mass evaporation rate as a function of time
and galactocentric distance xi(R_{GC},t). Upon extrapolating this formula to
smaller R_{GC} values, our results provide tentative evidence for a very high
xi value at small R_{GC}. Our results suggest that the corresponding mass loss
in the inner Galactic potential could be high and it should be accounted for
when star clusters pass within it. This has direct relevance to nuclear cluster
formation/growth via the infall of globular clusters through dynamical
friction. As an illustrative example, we estimate how the evaporation rate
increases for a ~10^5 solar masses globular cluster that decays through
dynamical friction into the galactic centre. We discuss the findings of this
work in relation to the formation of nuclear star clusters by inspiraling
globular clusters.
