Improved Bρ-defined isochronous mass spectrometry for mass measurements of exotic nuclei

Abstract: The technique of Bρ-defined isochronous mass spectrometry (Bρ-IMS), established at a storage ring, serves as a valuable tool for determining the masses of short-lived nuclei. In the previous Bρ-IMS experiments, the effects of magnetic field drifts have to be corrected in order to improve the mass resolving power of Bρ-IMS [Eur. Phys. J. A 59, 27 (2023)]. The correction procedures are complicated and require multiple reference ions with well-known masses in each injection, which may not be the cases in the measurements of exotic nuclei with tiny production yields. In this study, we propose a novel approach of Bρ-IMS that requires only one reference ion for mass determination in an individual injection, avoiding the tedious and complicated correction procedures. This approach achieves the mass precision comparable to that of previous Bρ-IMS results, and is approved to be suitable for future mass measurements of exotic nuclei with extremely low production yields.