  We have carried out theoretical studies of the phonons and spinons excitation
spectra of $Sr_2CuO_3 $ in term of a one-dimensional model with non-adiabatic
interaction magnetic and elastic subsystems using continuous time Monte Carlo
method. Two gaps in triplet excitation spectrum are found. The bond defects
concentration estimated is well agreement with the experimental data. The
formation of magnetic moment on site at low temperature $T_N \sim 5 K$ is
caused by freezing quantum spin liquid with correlation radius of
antiferromagnetic ordering $\xi/a \sim 300 - 500$
