Accurate mass measurements of very short-lived nuclei
Prerequisites for high-accuracy investigations of superallowed -decaysF. Herfurth1, A. Kellerbauer1, F. Ames2, G. Audi3, D. Beck4, K. Blaum4, G. Bollen5, O. Engels2, H.-J. Kluge4, D. Lunney3, R.B. Moore6, M. Oinonen7, E. Sauvan1, C. Scheidenberger4, S. Schwarz5, G. Sikler4, C. Weber4 and the ISOLDE Collaboration1
1 CERN, 1211 Geneva 23, Switzerland
2 Sektion Physik, Ludwig-Maximilians-Universität München, 85748 Garching, Germany
3 CSNSM-IN2P3-CNRS, 91405 Orsay Campus, France
4 GSI, Planckstraße 1, 64291 Darmstadt, Germany
5 NSCL, Michigan State University, East Lansing MI 48824-1321, USA
6 Department of Physics, McGill University, Montréal (Québec) H3A 2T8, Canada
7 Helsinki Institute of Physics, University of Helsinki, P.O. Box 9, 00014 Helsinki, Finland
(Received: 21 March 2002 / Published online: 31 October 2002)
Mass measurements of 34Ar, Kr, and 74,76Rb were performed with the Penning-trap mass spectrometer ISOLTRAP. Very accurate QEC-values are needed for the investigations of the -value of nuclear -decays used to test the standard model predictions for weak interactions. The necessary accuracy on the QEC-value requires the mass of mother and daughter nuclei to be measured with . For most of the measured nuclides presented here this has been reached. The 34Ar mass has been measured with a relative accuracy of . The QEC-value of the 34Ar decay can now be determined with an uncertainty of about 0.01%. Furthermore, 74Rb is the shortest-lived nuclide ever investigated in a Penning trap.
21.10.Dr - Binding energies and masses.
24.80.+y - Nuclear tests of fundamental interactions and symmetries.
© Società Italiana di Fisica, Springer-Verlag 2002