Further observations on the spatial emission properties of a microwave-induced plasma in argon

In a previous work, the authors postulated that the loss of analyte atoms from the plasma might result after initial ionization of analyte atoms (soon after their entry into the plasma) by subsequent drift of these ions in the inhomogeneous microwave field surrounding the discharge. Now, further experimental evidence has been found to support the authors hypothesis. The fact that an element as volatile as Hg is affected points to strong interaction of the accelerated analyte ions with the walls of the silica discharge tube used to contain the plasma.