Amplitude Values Different in Results vs. Mouse on Spectrum

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This topic contains 1 reply, has 2 voices, and was last updated by  Ronald Ouwerkerk 5 months ago.

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    Joshua Baker


    I am wondering what exactly is measured to produce a value for the amplitude of peaks in the numerical results table for AMARES.

    I am concerned because two peaks of similar height are shown having different amplitudes, one of which is twice the amplitude of the other peak. Additionally, the number presented for amplitude when hovering on a peak in the spectra are a different value than is present in the numerical results.

    I am hoping someone can clarify if there is a difference between what is presented in the spectra and what is listed in the numerical results. Also is it possible amplitude listen in the numerical results is in fact area under the curve?

    Thank you!


    Ronald Ouwerkerk

    Hi Joshua,

    You guessed it! The signal amplitude is the amplitude in the time domain and this is equal to the frequency domain peak area. If you want the peak amplitude, just divide the area (=time domain amplitude) by the width (Area = height * width at half maximum). The result is related to the unit of peak width (Hz), not an integral of the intensities over the peak foot-to-foot, but peak absolute peak areas are meaningless anyway.This method yields peak heights relative to the baseline (= the fit residual)


    Ronald Ouwerkerk

    Ronald Ouwerkerk
    National Institutes of Health (NIH)

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