Structure of Electron Bubbles in Liquid Helium under Pressure

We present here a simple calculation of electron-bubble radii in He Ii under pressure. An approximation for the two-particle density function is used which is identical to a scheme employed earlier for calculating the surface tension of ${\mathrm{He}}^4$ and surface states of ${\mathrm{He}}^3$ in solutions. There are no adjustable parameters, and the agreement with experiment is excellent. The approximation is proposed as a unifying model for all experiments involving helium surfaces.