HIGH-ACCURACY MASS MEASUREMENTS FOR A TEST OF THE STANDARD MODEL

摘要

The triple-trap mass spectrometer ISOLTRAP at ISOLDE/CERN has been applied for high-accuracy mass measurements of the short-lived superallowed β-decaying radionuclides 18{sup left}Ne, 22{sup left}Mg, 34{sup left}Ar, and 74{sup left}Rb. The atomic masses contribute to tests of the conserved-vector-current hypothesis of the weak interaction. They are also used to determine the value of the V{sub}(ud) element of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix and thus allow a test of the unitarity which possibly indicates physics beyond the Standard Model. present investigation, was the prototype experiment for the mass measurement of short-lived nuclides with an ion trap. Other experiments are CPT at Argonne National Laboratory [6], JYFLTRAP at IGISOL in Jyvaskyla [7], SHIPTRAP at GSI in Darmstadt [8], and since recently LEBIT at NSCL/MSU [9]. The experimental mass values from all these experiments contribute to different applications, mainly in nuclear physics for tests of mass models or the investigation of nuclear structure [1]. In this work, the contribution of atomic masses to a test of the weak interaction and the Standard Model is reviewed.