  Capture rates of compact objects were calculated by using a recent solution
of the Fokker-Planck equation in energy-space, including two-body resonant
effects. The fraction of compact objects (white dwarfs, neutron stars and
stellar black holes) was estimated as a function of the luminosity of the
galaxy from a new grid of evolutionary models. Stellar mass densities at the
influence radius of central supermassive black holes were derived from
brightness profiles obtained by Hubble Space Telescope observations. The
present study indicates that the capture rates scale as $\propto
M_{bh}^{-1.048}$, consequence of the fact that dwarf galaxies have denser
central regions than luminous objects. If the mass distribution of supermassive
black holes has a lower cutoff at $\sim 1.4\times 10^6$ M$_{\odot}$
(corresponding to the lowest observed supermassive black hole mass, located in
M32), then 9 inspiral events are expected to be seen by LISA (7-8 corresponding
to white dwarf captures and 1-2 to neutron star and stellar black hole
captures) after one year of operation. However, if the mass distribution
extends down to $\sim 2\times 10^5$ M$_{\odot}$, then the total number of
expected events increases up to 579 (corresponding to $\sim$ 274 stellar black
hole captures, $\sim$ 194 neutron star captures and $\sim$ 111 white dwarf
captures).
