Consider a system in which a non-plasma fluid (eg, gas, liquid, or supercritical fluid) consisting of a single isotope (for example, deuterium would be in the form of the D2 molecule) is struck with a small atom, stripped of all electrons. This atom also has a large amount of energy, enough to make fusion by tunneling significantly probable. The target would, of course, be neutral to the incoming positive charge at comparitively large distances. How would the electrons in the target molecule effect the probability of fusion? Would the Gamow-Sommerfeld factor apply fully here, or would the electrons inhibit fusion somehow? Or would they encourage it by allowing the fast positively charged atom to aproach closer to the target nucleus without being repelled by coulomb forces?