4s(3)P(2) metastable level density and temperature measurement in a low-density argon plasma

Temperature and density measurements of the 4s(3)P(2) argon metastable atom level in a weakly diffusion ionized argon plasma are presented and discussed. The steady state collisionless unmagnetized plasma is generated at a gas pressure of 50 mPa, extruded by hot filament DC discharges and diffused in a chamber of about 40 \ volume. The temperature is measured from the absorption linewidth and the density from the spectral absorption coefficient of a low-cost single-mode diode laser (801 479 nm) by scanning its frequency around the 4s(3)P(2)-4p(3)D(2) Arl transition.