  We investigated the influence of environment on cluster galaxies by examining
the alignment of the brightest cluster galaxy (BCG) position angle with respect
to the host cluster X-ray position angle. The cluster position angles were
measured using high spatial resolution X-ray data taken from the Chandra ACIS
archive, that significantly improved the determination of the cluster shape
compared to the conventional method of using optical images. Meanwhile, those
of the BCGs were measured using homogeneous dataset composed of high spatial
resolution optical images taken with Suprime-Cam mounted on Subaru 8m
telescope. We found a strong indication of an alignment between the cluster
X-ray emission and optical light from BCGs, while we see no clear direct
correlation between the degree of ellipticity of X-ray and optical BCG
morphologies, despite the apparent alignment of two elliptical structures. We
have also investigated possible dependence of the position angle alignment on
the X-ray morphology of the clusters, and no clear trends are found. The fact
that no trends are evident regarding frequency or degree of the alignment with
respect to X-ray morphology may be consistent with an interpretation as a lack
of dependence on the dynamical status of clusters.
