VIRTUAL WDS

'Virtual WDS' entails the synthesis of wavelength-dispersive spectra o n a computer screen using stored experimental pure-element spectra. Th e principal object is to facilitate the selection of optimal positions for background measurements, in order to minimise the effect of any i nterfering neighbouring lines. This approach is much more effective th an referring to wavelength tables and obviates the need to use 'real' instrument time for spectrometer scans to investigate each new case. W here interferences cannot be avoided completely, the size of the corre ction may be predicted. Stored experimental continuum spectra enable c orrections for background nonlinearity to be estimated (also for slope where background is measured on one side only, owing to the presence of an unavoidable interference on the other side). Further, analysis c onditions (counting times, etc.) required to achieve specified detecti on limits can be determined in advance.