A method to measure the transition energy ${\gamma }_t$ of the isochronously tuned storage ring

Abstract

The Isochronous Mass Spectrometry (IMS) is a powerful technique developed in heavy-ion storage rings for measuring masses of very short-lived exotic nuclei. The IMS is based on the isochronous setting of the ring. One of the main parameters of this setting is the transition energy ${\gamma }_t$. %The transition energy ${\gamma }_t$ plays an important role in the isochronous mass spectrometry (IMS). It has been a challenge to determine the ${\gamma }_t$ and especially to monitor the variation of ${\gamma }_t$ during experiments. In this paper we introduce a method to measure the ${\gamma }_t$ online during IMS experiments by using the acquired experimental data. Furthermore, since the storage ring has (in our context) a relatively large momentum acceptance, the variation of the ${\gamma }_t$ across the ring acceptance is a source of systematic uncertainty of measured masses. With the installation of two time-of-flight (TOF) detectors, the velocity of each stored ion and its revolution time are simultaneously available for the analysis. These quantities enabled us to determine the ${\gamma }_t$ as a function of orbital length in the ring. The presented method is especially important for future IMS experiments planned at the new-generation storage ring facilities FAIR in Germany and HIAF in China.

7 pages

References in corpus (3)

• Identification of the Lowest $T=2$, $J^{\pi =}{0}^{+}$ Isobaric Analog State in ${}^{52}$Co and Its Impact on the Understanding of $\beta$-Decay Properties of ${}^{52}$Ni
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Cited by in corpus (6)

• Heavy-Ion Storage Rings and Their Use in Precision Experiments with Highly Charged Ions
• $B\rho$-defined Isochronous Mass Spectrometry and Mass Measurements of ${}^{58}$Ni Fragments
• Particle identification and revolution time corrections for the isochronous mass spectrometry in storage rings
• Characterization of a double Time-Of-Flight detector system for accurate velocity measurement in a storage ring using laser beams
• Experimental Investigation of the Transition Energy ${\gamma }_t$ in the Isochronous Mode of the HIRFL-CSRe
• Improving the resolving power of Isochronous Mass Spectrometry by employing an in-ring mechanical slit