Recent Z-pinch experiments on ACE 4

Summary form only given. ACE 4 is a 4 MJ, 2 microsecond risetime, inductive energy storage (IES) generator equipped with typical diagnostics including calorimeters, time-resolved sensors (PCDs, XRDs, and silicon PIN diodes), and imagers (pinhole and spectra). ACE 4 uses a plasma opening switch (POS) to drive a close-coupled Z-pinch at currents of well over 3 MA. Current flows in the annular-plasma column of the POS for up to a microsecond and is then commutated to the central gas puff. Previously reported experiments discussed initial experiments using neon. This paper will present recent results using argon and argon-chlorine gas mixtures, emphasizing long implosion times (>200 ns), large initial radii (>3 cm), and non-shell (solid fill) gas distribution.