Depositing Lithium Films to Simulate ICF Reaction Products

A possible future experiment using Inertial Confinement Fusion (ICF) to measure low-energy light-ion nuclear cross sections has been simulated using the SUNY Geneseo Pelletron to activate a thin lithium target which was then rapidly evaporated, trapped, and detected. This experiment required a lithium film to be deposited in a vacuum of approximately 10^-5 Torr onto the surface of a thin tungsten foil. The films were produced by heating natural lithium pellets to 400 °C in a stainless-steel boat through which 20 A of current was passed. The evaporated lithium was contained inside a stainless-steel “house” inside the vacuum chamber, with a small opening on the top that allowed the lithium to reach the tungsten foil. The vacuum chamber was in an argon-filled glove bag which allowed the films to be briefly removed and handled since lithium reacts vigorously with oxygen and water vapor.