Phonon role in superconductivity of La(2-x)Sr(x)CuO(4) studied by inelastic x-ray scattering

This paper has been withdrawn by the authors, because we had probably observed some spurious intensity with x=0.29 sample (Fig.3(b)). This came out after further studies of the detailed x-dependence of the highest energy LO phonon branch in LSCO.