Dynamical state for 964 galaxy clusters from Chandra X-ray images
  The dynamical state of galaxy clusters describes if clusters are relaxed
dynamically or in a merging process of subclusters. By using archival images
from the Chandra X-ray Observatory, we derive a set of parameters to describe
the dynamical state for 964 galaxy clusters. Three widely used indicators for
dynamical state, the concentration index c, the centroid shift omega and the
power ratio P3/P0 are calculated in the circular central region with a radius
of 500 kpc. We also derive two adaptive parameters, the profile parameter kappa
and the asymmetry factor alpha, in the best fitted elliptical region. The
morphology index delta is then defined by combining these two adaptive
parameters, which indicates the dynamical state of galaxy clusters and has good
correlations to the concentration index c, the centroid shift omega, the power
ratio P3/P0, and the optical relaxation factor Gamma. For a large sample of
clusters, the dynamical parameters are continuously distributed from the
disturbed to relaxed states with a peak in the between, rather than the bimodal
distribution for the two states. We find that the newly derived morphology
index delta works for the similar fundamental plane between the radio power,
cluster mass and the dynamical state for clusters with diffuse radio
giant-halos and mini-halos. The offset between masses estimated from the
Sunyaev-Zeldovich effect and X-ray images depends on dynamical parameters. All
dynamical parameters for galaxy clusters derived from the Chandra archival
images are available on http://zmtt.bao.ac.cn/galaxy_clusters/dyXimages/.
