Fragmentation in the Time-of-Flight Mass Spectrometer

When fragmentation occurs prompdy (i.e., in the source and within a time frame that is indistinguishable from the time of ionization), the resultant fragment ions are 

Mass Dispersion of Product Ions in a Single-Stage Reflectron. If metastable fragmentation occurs in the first field-free drift region (Zq) of a single-stage reflectron instrument  

Product ions (wj,) have the same velocity as their precursor ions in the first drift region (Zq) where fragmentation occurs. Because the reflectron returns ions to the second drift region (Z ) with the same kinetic energy, product ions will also have this same velocity in the second drift region. Thus, the time that product ions spend in the linear regions of the mass spectrometer will be the same as their precursors  

However, these ions enter (and exit) the reflectron with kinetic energies equal to m /m )eV, and penetrate the reflectron to a depth of m /m d (where d is the average penetration depth of their precursors), so that the time that product ions spend in the reflectron is given by  

the total flight time of a product ion is given by  

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