Cara has two different integration methods which can be selected from the MonoScope menu under "Integrator-Method"
Both methods make use of the PeakModel.
Method 1: Model-based linear equation system
The peak model is used to deconvolute intensity contributions from nearby peaks so that the intensity coming from the peak is isolated. A linear system of equations represents the intensity of each peak which is composed of a sum of intensities contributed by the peak itself and any nearby peaks whose peak model predicts a contribution at the coordinate of the peakl. If all peaks have the same lineshapes, then the volume is proportional to the intensity of the peak. Therefore in this mode, the deconvoluted intensity of the peak is used to represent the peak volume. This is a fairly good approximation for 3D spectra where the lineshape is determined dominantly by the window function applied.
Method 2: Base rectangle intensity sum (2D only)
The base width of the PeakModel in each dimension defines the limits of a rectangular area whose intensity is integrated to give the volume. The rectangular area is the same for all peaks having the same model. This may be more appropriate when peaks in a 2D spectrum have varying lineshapes. The PeakModel should be chosen to include all intensity from the peaks with largest linewidth.