ISOLTRAP: An on-line Penning trap for mass spectrometry on short-lived nuclides

Abstract

ISOLTRAP is a Penning trap mass spectrometer for high-precision massmeasurements on short-lived nuclides installed at the on-line isotopeseparator ISOLDE at CERN. The masses of close to 300 radionuclideshave been determined up to now. The applicability of Penning trapmass spectrometry to mass measurements of exotic nuclei has beenextended considerably at ISOLTRAP by improving and developing thisdouble Penning trap mass spectrometer over the past two decades.The accurate determination of nuclear binding energies far from stabilityincludes nuclei that are produced at rates less than 100 ions/s andwith half-lives well below 100ms. The mass-resolving power reaches10(7) corresponding to 10keV for medium heavy nuclei and the uncertaintyof the resulting mass values has been pushed down to below 10(-8).The article describes technical developments achieved since 1996and the present performance of ISOLTRAP.