We investigated the dynamical evolutions of star clusters with primordial
binaries by means of GORILLA, an N-body simulation code we develop from
scratch. We simulated eleven clusters consisting of N=16384 equal-mass
stars. The clusters have primordial binaries whose binding energies are
equal in each cluster. Six clusters of these contain 10 percent (in mass)
primordial binaries with 1kT, 3kT, 10kT, 30kT, 100kT, and 300kT, three
clusters contain 3 percent primordial binaries with 3kT, 30kT, and 300kT,
and two clusters contain 30 percent primordial binaries with 3kT and 30kT,
where 1.5kT is average stellar kinetic energy. We found that, in both soft
(< 3kT) and hard (> 300kT) limits, clusters experiences deep core collapse
when the clusters contain 10 percent primordial binaries. On the other
hands,
in the intermediate hardness (10-100kT), the core collapses halt
halfway. The
boundary of the depth of core collapse depends on the mass fraction of the
primordial binaries. The cluster with 3kT primordial binaries
experiences shallow
core collapse when the mass fraction is 30 percent. The core radii at
the halt
can be explained by their energy budget.