W. R. Plass

Measurement of the {beta}{sup +} and Orbital Electron-Capture Decay Rates in Fully Ionized, Hydrogenlike, and Heliumlike {sup 140}Pr Ions

We report on the first measurement of the beta+ and orbital electron-capture decay rates of 140Pr nuclei with the simplest electron configurations: bare nuclei, hydrogenlike, and heliumlike ions. The measured electron-capture decay constant of hydrogenlike 140Pr58+ ions is about 50% larger than that of heliumlike 140Pr57+ ions. Moreover, 140Pr ions with one bound electron decay faster than neutral 140Pr0+ atoms with 59 electrons. To explain this peculiar observation one has to take into account the conservation of the total angular momentum, since only particular spin orientations of the nucleus and of the captured electron can contribute to the allowed decay.

Schottky mass measurements of heavy neutron-rich nuclides in the element range 70 <= Z <= 79 at the GSI Experimental Storage Ring

D. Shubina, 2, 3 R.B. Cakirli, 4 Yu.A. Litvinov, 3 K. Blaum, C. Brandau, 5 F. Bosch, J.J. Carroll, R.F. Casten, D.M. Cullen, I.J. Cullen, A.Y. Deo, B. Detwiler, C. Dimopoulou, F. Farinon, H. Geissel, 11 E. Haettner, M. Heil, R.S. Kempley, C. Kozhuharov, R. Knobel, J. Kurcewicz, N. Kuzminchuk, S.A. Litvinov, Z. Liu, R. Mao, C. Nociforo, F. Nolden, Z. Patyk, W.R. Plass, A. Prochazka, M.W. Reed, 15 M.S. Sanjari, 16 C. Scheidenberger, 11 M. Steck, Th. Stohlker, 17, 18 B. Sun, 19 T.P.D. Swan, G. Trees, P.M. Walker, 20 H. Weick, N. Winckler, 3 M. Winkler, P.J. Woods, T. Yamaguchi, and C. Zhou Max-Planck-Institut fur Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany Fakultat fur Physik und Astronomie, Universitat Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany GSI Helmholtzzentrum fur Schwerionenforschung, Planckstrase 1, 64291 Darmstadt, Germany Department of Physics, University of Istanbul, Istanbul, Turkey ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum fur Schwerionenforschung, 64291 Darmstadt, Germany US Army Research Laboratory, 2800 Powder Mill Road, Adelphi MD, USA Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520, USA Schuster Laboratory, University of Manchester, Manchester M13 9PL, United Kingdom Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom Youngstown State University, One University Plaza, Youngstown, Ohio 44555, USA II Physikalisches Institut, Justus-Liebig-Universitat Giesen, 35392 Giesen, Germany School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China National Centre for Nuclear Research, PL-00681 Warsaw, Poland Department of Nuclear Physics, R.S.P.E., Australian National University, Canberra ACT 0200, Australia Goethe-Universitat Frankfurt, 60438 Frankfurt, Germany Friedrich-Schiller-Universitat Jena, 07737 Jena, Germany Helmholtz-Institut Jena, 07743 Jena, Germany School of Physics and Nuclear Energy Engineering, Beihang University, 100191 Beijing, PRC CERN, CH-1211 Geneva 23, Switzerland Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan Storage-ring mass spectrometry was applied to neutron-rich Au projectile fragments. Masses of Lu, Hf, Ta, W, and Re nuclei were measured for the first time. The uncertainty of previously known masses of W and Os nuclei was improved. Observed irregularities on the smooth two-neutron separation energies for Hf and W isotopes are linked to the collectivity phenomena in the corresponding nuclei.

SHE Research with Rare-Isotope Beams, Challenges and Perspectives, and the New Generation of SHE Factories

SHE research at GSI is strongly inspired by the ideas of Walter Greiner. He developed the theoretical concept of cold heavy-ion fusion, the use of magic nuclei for SHE production which was successful to create super heavy elements at GSI. Later the concept of magic nuclei for SHE production has been applied to hot fusion at JINR Dubna. A large region of super heavy elements extending even beyond element 114 has been discovered. The discovery of the spherical SHE is still waiting. New ideas to surpass the present limit at Z = 118 and to access the region of spherical SHE are needed. In this paper the perspectives for SHE production with rare-isotope beams will be discussed in the light of the new generation of SHE factories with intense beams. New experimental developments such as a setup for spectroscopic studies at the GSI SuperFRS and a next-generation in-flight separator with direct isotope identification will be addressed.

A CONCEPTUAL DESIGN STUDY OF A NEXT GENERATION SEPARATOR FOR THE IN-FLIGHT SEPARATION OF SUPERHEAVY NUCLEI

After more than 25 years of the successful operation of SHIP in heavy and superheavy element research, it is sue time for the developement of a next-generation in-flight separator for fusion and transfer products, primarily for heavy and superheavy elements. This work is triggered by new developments including accelerators for beams of highest intensity, the availability of strong beams of radioactive isotopes at near coulomb barrier energies, and the recent developement for efficient ion catcher-cooler systems with the capability of mass identification and measurement.

Mass measurement of radionuclides near the endpoint of the rp-process at SHIPTRAP

Gleb Vorobjev, Dieter Ackermann, Dietrich Beck, Klaus Blaum, Michael Block, Ankur Chaudhuri, Zhenyu Di, Sergey Eliseev, Rafael Ferrer, Dieter Habs, Frank Herfurth, Fritz Hessberger, Sigurd Hofmann, H.-Jürgen Kluge, Giancarlo Maero, Ana Martín, Gerrit Marx, Marco Mazzocco, Jürgen B. Neumayr, Yuri Novikov, Wolfgang Plass, Christian Rauth, Daniel Rodríguez, Christoph Scheidenberger, Lutz Schweikhard, Michael Sewtz, Peter Thirolf, Wolfgang Quint, and Christine Weber.