CAPS PMssa Monitor (Particle Optical Extinction and Scattering)

Based on the CAPS PMex particle extinction monitor, this instrument incorporates an integrating sphere within the optical path, allowing for an accurate and precise measurement of particle scattering with minimal truncation effects. Operation is identical to the PMex monitor except for the need for periodic calibration of the scattering channel. With knowledge of the particle size distribution of the sample, SSA can be measured with an accuracy of better than ±0.03 at high values of SSA (typical of non-urban air masses) and ±0.01 as SSA approaches zero (typical of fresh soot emissions from combustion sources).