The second stability region of quadrupole mass filter with square wave shape power supply.

Abstract

The ion-optical properties of the second stability region ($q=4.5$) formed by the square wave shape potential with a duty cycle of 50% are studied as applied to the operation of a linear ion trap. The stability diagram is presented in detail, the stability parameters ${\beta }_x$ and ${\beta }_y$, which determine the spectrum of ion oscillations, are calculated; the pseudopotential well-depth for this zone is given. The LIT acceptances for sinusoidal and rectangular wave forms are shown for comparison. Based on the obtained data, the excitation contour is modeled using the trajectory method, where a resolution of 25,000 without using gas damping is found.