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Agilent 5975 MSD Autotune Report Readings

Question asked by pcke2000 on May 12, 2020

I have couple of questions regarding Agilent 5975 MSD (run on MassHunter) Autotune Report. Please see the attached. It looks like for m/z 69, 219, and 502, there are two sets of data on the report. The Abund and Rel Abund (m/z 219) numbers are slightly different between the two data sets. 


I guess the two sets of data are collected at different times. Is it correct to say that the top set is collected during mass assignment and the bottom set is obtained during Scan mode (of all peaks across the set mass range)?


So when I evaluate the Autotune results and check 'Rel Abund', which set should I use? I found in an online teaching document by Agilent, it is recommended to use the top set, could anyone explain to me why?


Thank you very much!