  Reaction- and interaction cross sections of 17C on a carbon target have been
reanalyzed by use of the modified Glauber model. The analysis with a deformed
Woods-Saxon density/potential suggests a big deformation structure for 17C. The
existence of a tail in the density distribution supports its possibility of
being a one-neutron halo structure. Under a deformed core plus single-particle
assumption, analysis shows a dominant d-wave of the valence neutron in 17C. Key
words Cross section, Glauber model, Density distribution, Halo, Deformation.
