Globular cluster evolution in M87 and fundamental plane ellipticals

The globular cluster population in M87 has decreased measurably throughdynamical evolution caused by relaxation, binary heating and time-dependenttidal perturbation. For fundamental plane ellipticals in general, clusterpopulations evolve more rapidly in smaller galaxies because of the higher massdensity. A simple evolutionary model reproduces the observed trend in specificfrequency with luminosity for an initially constant relationship. Fits of theoretically evolved populations to M87 cluster data from McLaughlinet al. (1994) show the following: 1) dynamical effects drive evolution in theinitial mass and space distributions and can account for the large core in thespatial profile as well as producing radial-dependence in the mass spectrum; 2)evolution reduces S_N by 50% within 16 kpc and 35% within 50 kpc, implying thatS_N was initially 26 in this region. We estimate that 15% of the `missing'clusters lie below the detection threshold with mass less than 10^5 M_sun.