  We use archival ALMA observations of the CO(2-1) and SiO(5-4) molecular line
emissions of AGB star R Hya to illustrate the relative contributions of
rotation, expansion and line broadening to the morphology and kinematics of the
circumstellar envelope (CSE) within some ~70 au (~0.5 arcsec) from the centre
of the star. We give evidence for rotation and important line broadening to
dominate the inner region, within ~14 au (~100 mas) from the centre of the
star. The former is about an axis that projects a few degrees west of north and
has a projected rotation velocity of a few km/s. The latter occurs within some
7-14 au (50-100 mas) from the centre of the star, the line width reaching two
to three times its value outside this region. We suggest that it is caused by
shocks induced by stellar pulsations and convective cell granulation. We show
the importance of properly accounting for the observed line broadening when
discussing rotation and evaluating the radial dependence of the rotation
velocity.
