Patent ID: 7956320

Claim:
A data processor for a mass spectrometer, for processing data obtained by a mass spectrometer capable of performing an MS n analysis in which an ion having a specific mass-to-charge ratio is selected as a precursor ion from among ions obtained by an MS n-1 (where n is an integer equal to or more than two) analysis and an MS n analysis of an ion generated by a dissociation operation for the precursor ion is performed, comprising: a) an MS n spectrum creator for creating spectrum data for displaying an MS n spectrum based on data obtained by an MS n analysis; b) a mass-to-charge ratio difference calculator for calculating each difference between a mass-to-charge ratio of all or a portion of peaks appearing on the MS n spectrum and a mass-to-charge ratio of a precursor ion of the MS n analysis and/or a precursor ion of an MS 2 analysis through MS n-1 analysis (where n is equal to or more than three in this case) which have been a basis of a creation of the MS n analysis' precursor ion; c) an MS n mass-to-charge ratio difference spectrum creator for creating mass-to-charge ratio difference spectrum data for displaying an MS n mass-to-charge ratio difference spectrum having a peak at a position of each mass-to-charge ratio difference obtained by the mass-to-charge ratio difference calculator; and d) a spectrum merge section for creating a spectrum in which the MS n mass-to-charge ratio difference spectrum and the MS n spectrum are overlapped or combined so that each peak appearing on both spectra can be visually discriminable, and the data processor for a mass spectrometer displaying the spectrum created by the spectrum merge section on a display screen.