Target and lithium-lens of the AA

As an alternative to the "Magnetic Horn", a "Current Lens" was used to focus antiprotons emerging from the production target. Lithium was chosen as it is the lightest metal, for minimal scattering and losses. This first version had at its core a lithium rod, 34 mm in diameter and 115 mm long. It is surrounded by a pulse transformer, which induced currents up to 850 kA. Later, with LEAR as the only client, in a more modest version a 20 mm lithium rod was pulsed to 480 kA.