Shakeup Effects on Photoluminescence from the Wigner Crystal
  We develop a method to compute shakeup effects on photoluminescence in a Wigner crystal from localized holes. Our method treats the lattice electrons and the tunneling electron on an equal footing, and uses a quantum-mechanical calculation of the collective modes that is realistic throughout the Brillouin zone. We find that shakeup produces a series of sidebands that may be identified with maxima in the collective mode density of states, and definitively distinguishes the crystal state from a liquid state. We also find a shift in the main luminescence peak, that is associated with lattice relaxation in the vicinity of a vacancy. 
D.Z. Liu, H.A. Fertig, and S. Das Sarma