Köln 2004 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 2: Nuclear Structure/Spectroscopy I
HK 2.3: Gruppenbericht
Montag, 8. März 2004, 16:45–17:15, A
Absolute mass measurements of exotic nuclides at 10−8 precision with ISOLTRAP — •Klaus Blaum — CERN, Division EP, 1211 Geneva 23, Switzerland — GSI, Planckstraße 1, 64291 Darmstadt, Germany
ISOLTRAP is a Penning trap mass spectrometer installed at ISOLDE/CERN for on-line mass measurements of short-lived radionuclides. The precise determination of nuclear binding energies far from stability includes nuclei that are produced at rates of 100 ions/s and with half-lives well below 100 ms. The mass resolving power reaches 107 and the uncertainty of the resulting mass values has been pushed down to 1·10−8 [1,2].
A number of scientific highlights have been obtained recently, as e.g. the mass measurement of 32Ar (T1/2 = 98 ms) and 74Rb (T1/2 = 65 ms). Both provide important input for fundamental tests of the weak interaction, for example with regards to the conserved vector current (CVC) hypothesis and the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Furthermore, the high resolving power of ISOLTRAP allowed us to prepare an isomerically pure ion beam. This opens a new field in nuclear physics at low energies. In combination with the resonant ionization laser ion source we were able to solve via high-precision mass measurements the long-outstanding assignment puzzle between the ground state and the two low-lying isomeric states in 70Cu. The status of ISOLTRAP as well as recent results will be presented.
[1] F. Herfurth et al., J. Phys. B 36 (2003) 931.
[2] K. Blaum et al., Nucl. Instrum. Methods 204 (2003) 478.