The Kinematic Energy Loss

K denotes the kinematic factor for the elastic scattering process. Thus, in RBS, a projectile of known mass and known energy is employed, and by measuring the 

If a target contains two masses that differ by a small amount AM2 the difference in the energy of the projectile after collision is given by 

The largest change in K for a given AM2 occurs when 0=180°, and so large scattering angles maximise the mass discrimination of the technique. 

If A j is set equal to 5E, the minimum energy separation that can be resolved experimentally, then the mass resolution of the system, 8M2, is  

The mass resolution at the sample surface is usually determined primarily by the detector resolution. 

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