Decay of metastable argon atoms in the afterglow plasma

Time-dependent studies of the particle density in 1s(5) state of Ar plasma are performed using single-frequency laser absorption probing. The applied voltage on the 400Pa striated plasma (current: 0.01-20 mA DC) is cut off, a nd from the decay curve studies of the density, the following rates are obt ained: the rate of collision between 1s(5)-1s(5) metastable atoms alpha (cm (3) s(-1)) = (2.0 +/- 0.5) x 10(-8), the rate of collision between 1s(5) me tastable atoms and electrons F-e (cm(3) s(-1)) = 3.8 x 10(-7) and the elect ron loss rate in the afterglow gamma(e)(s(-1)) = 250 + 1.0 x 10(-7) x n(e), where n(e) (cm(-3)) is the electron density. We also present the time-depe ndent n(e) behavior in one striation peak using values obtained here.