  We determine a constraint on the growth factor by measuring the damping of
the baryon acoustic oscillations in the matter power spectrum using the Sloan
Digital Sky Survey luminous red galaxy sample. The damping of the BAO is
detected at the one sigma level. We obtain \sigma_8D_1(z=0.3) =
0.42^{+0.34}_{-0.28} at the 1\sigma statistical level, where \sigma_8 is the
root mean square overdensity in a sphere of radius 8h^{-1}Mpc and D_1(z) is the
growth factor at redshift z. The above result assumes that other parameters are
fixed and the cosmology is taken to be a spatially flat cold dark matter
universe with the cosmological constant.
