  In the search for a composite Higgs boson in walking technicolor models, many
flavor QCD, in particular with $N_f=8$, is an attractive candidate, and has
been found to have a composite flavor-singlet scalar as light as the pion.
Based on lattice simulations of this theory with the HISQ action, we will
present our preliminary results on the scalar decay constant using the
fermionic bilinear operator, and on the mass of the lightest baryon state which
could be a dark matter candidate. Combining these two results, implications for
dark matter direct detection are also discussed.
