Detection in FT-ICR-MS

An interesting correlation exists between the transient signal and the pressure in the ICR cell. [197,201] In a perfect vacuum, the orbiting motion would solely be 

Note Besides from elongated deteetion intervals, mass aeeuraey of FT-ICR-MS also benefits by a faetor of 3-10 from internal mass ealibration compared to external calibration (Chap. 3.3.5). External calibration works the better, the closer the cyclotron radius and the number of calibrant ions fit the conditions of the intended analytical measurements. [200] 

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