Electric and magnetic field optimization procedure for Penning trap mass spectrometers

TL;DR

This paper presents an experimental method to optimize electric and magnetic fields in Penning trap mass spectrometers, reducing systematic errors for more precise measurements.

Contribution

It introduces a procedure to minimize field imperfections in Penning traps by measuring ion frequencies and adjusting correction parameters.

Findings

Reduced frequency shifts after optimization

Improved mass measurement precision

Validated procedure for field correction

Abstract

Significant systematic errors in high-precision Penning trap mass spectrometry can result from electric and magnetic field imperfections. An experimental procedure to minimize these uncertainties is presented for the on-line Penning trap mass spectrometer ISOLTRAP, located at ISOLDE/CERN. The deviations from the ideal magnetic and electric fields are probed by measuring the cyclotron frequency and the reduced cyclotron frequency, respectively, of stored ions as a function of the time between the ejection of ions from the preparation trap and their capture in the precision trap, which influences the energy of their axial motion. The correction parameters are adjusted to minimize the frequency shifts.