Accurate velocity determination of stored ions in CSRe by resolving the non-isochronicity of time-of-flight detectors

摘要: Accurate velocity determination of stored ions in storage rings plays a key role for nuclear mass measurements using the technique of B$\rho$-defined isochronous mass spectrometry (Bρ-IMS). However, the accuracy and precision of the ion's velocity are seriously deteriorated by the non-isochonicity of the time-of-flight (TOF) detectors. In this paper, the non-isochonicity is described by a correlation function between the time-delay difference, $t_d$, of the two TOF detectors and the orbital length, $C$, of the stored ions. The obtained correlation functions, t_d∽ C, allow for accurate determination of the ion's velocity which is then used for mass calibration in the Bρ-IMS technique. The present data analysis method is proved to be capable of resolving the effects of the non-isochronicity of TOF detectors.