The separation with aggregating in Raman spectroscopy refers to the process of separating the Raman signal from the scattered laser light using a technique called spectral aggregation. In spectral aggregation, the scattered light is passed through a grating that disperses it into its component wavelengths. The Raman signal is then separated from the scattered laser light by using a filter or a notch filter that only passes light at the Raman shift wavelengths.

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