An HSC view of the CMASS galaxy sample. Halo mass as a function of
  stellar mass, size and S\'ersic index
  Aims. We wish to determine the distribution of dark matter halo masses as a
function of the stellar mass and the stellar mass profile, for massive galaxies
in the BOSS CMASS sample. Methods. We use grizy photometry from HSC to obtain
S\'ersic fits and stellar masses of CMASS galaxies for which HSC weak lensing
data is available, visually selected to have spheroidal morphology. We apply a
cut in stellar mass, $\log{M_*/M_\odot} > 11.0$,selecting $\sim$10, 000
objects. Using a Bayesian hierarchical inference method, we first investigate
the distribution of S\'ersic index and size as a function of stellar mass.
Then, making use of shear measurements from HSC, we measure the distribution of
halo mass as a function of stellar mass, size and S\'ersic index. Results. Our
data reveals a steep stellar mass-size relation $R_e \propto M_*^{\beta_R}$,
with $\beta_R$ larger than unity, and a positive correlation between S\'ersic
index and stellar mass: $n \propto M_*^{0.46}$. Halo mass scales approximately
with the 1.7 power of the stellar mass. We do not find evidence for an
additional dependence of halo mass on size or S\'ersic index at fixed stellar
mass. Conclusions. Our results disfavour galaxy evolution models that predict
significant differences in the size growth efficiency of galaxies living in low
and high mass halos.
