Eur. Phys. J. A (2009) 42: 351-359
https://doi.org/10.1140/epja/i2009-10835-1

Regular Article - Experimental Physics

Preparing a journey to the east of ²⁰⁸Pb with ISOLTRAP: Isobaric purification at A = 209 and new masses for ^211-213Fr and ²¹¹Ra

¹ Physics Department, CERN, 1211, Geneva 23, Switzerland
² CSNSM-IN2P3-CNRS, Université de Paris Sud, Orsay, France
³ IFIC, CSIC-Universidad de València, València, 46071, Spain
⁴ Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026, Debrecen, Hungary
⁵ GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse 1, 64291, Darmstadt, Germany
⁶ CENBG, Université Bordeaux 1/CNRS/IN2P3, 33175, Gradignan Cedex, France
⁷ Max-Planck-Institut für Kernphysik, 69117, Heidelberg, Germany
⁸ Institut für Physik, Johannes Gutenberg-Universität, 55099, Mainz, Germany
⁹ Institut für Physik, Ernst-Moritz-Arndt-Universität, 17487, Greifswald, Germany
¹⁰ Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense, 28040, Madrid, Spain
¹¹ Department of Physics and Astronomy, University of Aarhus, 8000, Aarhus, Denmark
¹² NSCL, Michigan State University, East Lansing, MI, USA

^* e-mail: kowalska@cern.ch

Received: 5 January 2009
Revised: 12 May 2009
Accepted: 17 June 2009
Published online: 26 July 2009

Abstract

With the Penning trap mass spectrometer ISOLTRAP, located at ISOLDE/CERN, preparatory work has been performed towards mass and decay studies on neutron-rich Hg and Tl isotopes beyond N = 126 . The properties of these isotopes are not well known because of large isobaric contamination coming mainly from surface-ionised Fr. Within the studies, production tests using several target-ion source combinations were performed. It was furthermore demonstrated around mass number A = 209 that the resolving power required to purify Fr is achievable with ISOLTRAP. In addition, masses of several isobaric contaminants, ^211-213Fr and ²¹¹Ra , were determined with a three-fold improved precision. The results influence masses of more than 20 other nuclides in the ²⁰⁸Pb region.