  The alignment between brightest cluster galaxies (BCGs) and host clusters can
reveal the mystery of formation and evolution for galaxy clusters. We measure
cluster orientations in optical based on the projected distribution of member
galaxies and in X-ray by fitting the morphology of intra-cluster medium (ICM).
Cluster orientations determined in the two wavelengths are generally
consistent. The orientation alignment between BCGs and host clusters is
confirmed and more significant than previous works. We find that BCGs are more
aligned with cluster orientations measured in X-ray than those from optical
data. Clusters with a brighter BCG generally show a stronger alignment. We
argue that the detected redshift evolution of the alignment is probably caused
by observational bias rather than intrinsic evolution. The alignment is not
related to the ellipticity of BCGs, and the richness, ellipticity and dynamical
state of host clusters. The strong alignment between BCGs and morphology of
ICMs may be the consequence of the co-evolution between the central massive
galaxy and host clusters.
