Particle mass analyser
A Particle mass analyser '' is an instrument for classifying aerosol particles according to their mass-to-charge ratio using opposing electrical and centrifugal forces. This allows the classifier to select particles of a specified mass-to-charge ratio independent of particle shape.
It one of the three types of monodisperse aerosol classifier, the others being the Ion [mobility spectrometry#Differential mobility analyzer|differential mobility analyser], and the aerodynamic aerosol classifier. The corresponding three quantities are related by the expression τ = mB, where τ is relaxation time, m is mass and B is mobility.
Further work improved the technique by engineering the centrifugal force to match the electrostatic force across the whole classification region, thus increasing the throughput.