Towards Ultimate Sensitivity for Rare Isotope Mass Spectrometry Using the Single Ion Penning Trap
Scott Campbell, Michigan State University
Precision mass measurements of rare isotopes are an essential input for almost all areas of nuclear physics research [1,2]. Modern mass spectrometry techniques are often unable to access measurements of the most exotic isotopes due to half-life limitations and ability to acquire sufficient statistics. At the Low Energy Beam Ion Trap (LEBIT) group at the Facility for Rare Isotope Beams, utilizes Penning trap mass spectrometry: the most precise mass measurement method known to date [3]. The Single Ion Penning Trap project at LEBIT takes advantage of the narrowband Fourier transform ion cyclotron resonance technique [4] to access, in principle, a complete mass measurement of a single ion. This technique measures the image current of ions in the Penning trap, and can be extended to single ion resolution with a cryogenic high-quality factor superconducting RLC resonator circuit. The resulting signal can be weak, and may be subject to noise on the order of the signal itself. Current work uses a priori knowledge and supervised machine learning to differentiate real signals from noise. Additionally, neural networks trained with data simulated to match SIPT characteristics are used to determine the percent composition for different numbers of ions composing a signal. This is ultimately used to validate the single ion resolution for SIPT. The specifics of these algorithms and neural networks, their performance, and results on experimental data will be presented.
This work was conducted with the support of Michigan State University and the National Science Foundation under Grants No. PHY-1102511, No. PHY-1126282, and PHY-2111185.
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