Method of mass analyzing a sample by use of a quistor

US4882484A · kind A · utility

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventors

• Jochen Franzen · Bremen, DE
• Reemt-Holger Gabling · Stuhr, DE
• Gerhard Heinen · Tarmstedt, DE
• Gerhard Weiss · Ludwigshafen, DE

Key dates

• Filing date: Oct 31, 1988
• Grant date: Nov 21, 1989
• Expiry date: Oct 31, 2008

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J49/429
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

In a quadrupole ion store (QUISTOR), a sample is analyzed by increasing the mplitude of the harmonic, or "secular", oscillations of selected stably trapped ions so that they leave the trapping field. In a preferred embodiment, deviations from the ideal electrode geometry are incorporated into the QUISTOR to produce resonance phenomena between the r and z secular oscillations, thereby increasing the amplitude of oscillations in the z direction.