Phase-Imaging Ion-Cyclotron-Resonance technique at the JYFLTRAP double Penning trap mass spectrometer

Abstract

The Phase-Imaging Ion-Cyclotron-Resonance (PI-ICR) technique has been commissioned at the JYFLTRAP double Penning trap mass spectrometer. This technique is based on projecting the ion motion in the Penning trap onto a position-sensitive multichannel-plate ion detector. Mass measurements of stable 85 Rb + and 87 Rb + ions with well-known mass values show that relative uncertainties ∆m/m ≤ 7 · 10 −10 are possible to reach with the PI-ICR technique at JYFLTRAP. The significant improvement both in resolving power and in precision compared to the conventional Time-of-Flight Ion Cyclotron Resonance technique will enable measurements of close-lying isomeric states and of more exotic isotopes as well as ultra-high precision measurements required, e.g., for neutrino physics. In addition, a new phase-dependent cleaning method based on the differences in the accumulated cyclotron motion phases has been demonstrated with short-lived 127 In + and 127m In + ions.

Exploring the mass surface near the rare-earth abundance peak via precision mass measurements at JYFLTRAP

“…The method can result in a three-fold gain in precision. The TOF-ICR technique has been used exclusively for mass measurements at JYFLTRAP until 2018 when the newer phase-imaging ion-cyclotron-resonance (PI-ICR) technique [48] was successfully commissioned and implemented at JYFLTRAP [49]. The measurements using the two methods in this work are further described in the following subsections II B 2 and II B 3.…”

Recent experiments at the JYFLTRAP Penning trap

“…JYFLTRAP [5][6][7] is a cylindrical double Penning trap mass spectrometer located inside a 7 T superconducting solenoid at the IGISOL facility [9]. The continuous radioactive ion beam from IGISOL is first mass-separated using a dipole magnet, which is usually sufficient to select the mass number of interest A.…”

“…A new technique to determine the ion's cyclotron resonance frequency, the Phase-Imaging Ion Cyclotron Resonance (PI-ICR) technique [15], was commissioned at JYFLTRAP in 2017, see Ref. [7]. A position-sensitive MCP ion detector with a delay-line anode (DLD40) from RoentDek GmbH [16] was installed behind the traps, and the extraction optics was modified accordingly.…”

“…The mass measurements of silver isotopes at JYFLTRAP were performed with the PI-ICR technique [7,15]. Phase accumulation times in the measurement trap had to be selected for each case individually depending on the excitation energies of the isomers to fully separate them.…”

“…Mass measurements with a good precision of ≤ 10 keV/c 2 are also needed to study subtle changes in nuclear structure [2,3] or to provide accurate inputs for astrophysical reaction network calculations [4]. In this contribution, we review the recent activities at the JYFLTRAP double Penning trap mass spectrometer [5][6][7] located at the Ion Guide Isotope Separator On-Line (IGISOL) facility [8,9] in the JYFL Accelerator Laboratory of the University of Jyväskylä, Finland.…”