Fig. 2.

Phase velocity and broadening of the transverse acoustic-like excitations in a LJ glass. Frequency dependence of phase velocity (red circles in A) and FWHM (red circles in B) of the transverse acoustic-like excitations of the studied LJ glass. The dashed lines in B emphasize different regimes: ∼ω² at high frequencies and ∼ω⁴ at low frequencies. The transition between the two regimes appears at the frequency where the phase velocity in A shows a minimum.