Interpretation of Photoejection Experiments and the Well Depth of Electronic Bubbles in Liquid Helium

A calculation of the optical-absorption cross section of electronic bubbles in liquid helium is presented as a function of energy and pressure for various assumed values of the zero-pressure well depth $V_0\mathrm{}\left(0\right)\mathrm{}$. It is shown that a simple interpretation of the Northby-Zipfel-Sanders experiments on "photoejection" can be based on a value of $V_0\mathrm{}\left(0\right)\mathrm{}$ of 0.95 eV, varying with pressure (i.e., density) according to either the optical or the Wigner-Seitz approximation. We suggest an interpretation in which the electron is not necessarily released from the bubble, and predict that these experiments performed at 12 $\mu$ (zero pressure) to 25 $\mu$ (15 atm) would show a ${10}^2$-larger effect.