A multi-reflection time-of-flight mass spectrometer for mass measurements of short-lived nuclei

摘要

In order to determine binding energies of short-lived nuclei we have developed a time-of-flight mass spectrometer of high mass resolving power m/Δm. This spectrometer achieves a very long ion flight path by repeatedly reflecting ions between two electrostatic ion mirrors. The nuclei to be investigated are produced in heavy ion fragmentations and separated in-flight by a fragment separator. These energetic ions are thermalized in a catcher gas cell injected into an RF ion-guide and then into an ion trap to be cooled, bunched and entered into the time-of-flight spectrometer. This technique should allow to determine the masses of short-lived nuclei with high efficiency. Using stable ions, the so far achieved mass resolving power m/Δm exceeded 65,000.