What is the difference between TIC and TICC?

Question

I have picked up a textbook on mass spectrometry, and I am finding it did not clearly distinguish between total ion chromatogram (TIC) and total ion current chromatogram (TICC) in the section (1.3 Ion Chromatograms) I just read. I suspect there was some sort of typo, but I don't have the experience to tell yet.

Here is an abridged excerpt from the textbook that has confused me:

The total ion current (TIC) can either be measured by a hardware TIC monitor before mass analysis (nA to uA range), or its equivalent can be reconstructed or extracted after mass analysis. [...] Thus, the TIC represents a measure of the overall intensity of ion production of ion production or of mass spectral output as a function of time, respectively. The TIC obtained by means of data reduction, [...], is termed total ion chromatogram (TIC). The term total ion current chromatogram (TICC) refers to a chromatogram obtained by plotting the total ion detected in each of a series of mass spectra recorded as a function of retention times of the chromatographically separated components of a mixture (which is essentially implicated by: TIC).

I would like to an explanation of the difference between total ion chromatogram (TIC), and total ion current chromatogram (TICC).

Answer 1

Ok, I had to read the actual text on pages 11 and 12 of the textbook link to understand.

TIC - In the olden days of mass spectrometers there was a way to measure the ion current from the sample (all masses). This total current is the current of all masses that is being injected into the mass spectrometer. Since the current in detector was also being measured, the spectra is plotted as the ratio of currents vs the mass (scan time).

TICC - The current from the sample is ignored and the spectra is just plotted as current in the detector vs mass (scan time).