Tarifeno-Saldivia, A (Tarifeno-Saldivia, Ariel)1,2; Pavez, C (Pavez, Cristian)3,4; Moreno, J (Moreno, Jose)3,4; Soto, L (Soto, Leopoldo)3,4................1. Univ Concepcion, Concepcion 4191669, Chile 2. Ctr Res & Applicat Plasma Phys & Pulsed Power, Santiago 6500687, Chile 3. Comis Chilena Energia Nucl, Thermonucl Plasma Dept, Santiago, Chile 4. Univ Talca, Ctr Res & Applicat Plasma Phys & Pulsed Power P4, Curico 685, ChileDynamics in the radial phase and plasma conditions in the pinch phase have been studied using interferometry in a plasma focus device that operates in the range of tens of joules of stored energy in the capacitor bank and tens of kiloamperes, PF-50J. The results of these experiments using deuterium as filling gas, together with the simultaneous measurements of neutron production, are reported in this paper. The results show that the typical dynamics, pinch conditions, and electron density observed in larger machines are also present in this experiment operated at only tens of joules.