Norbert Wiehl

  • Citations Per Year
Learn More
To establish Boron Neutron Capture Therapy (BNCT) for non-resectable liver metastases and for in vitro experiments at the TRIGA Mark II reactor at the University of Mainz, Germany, it is necessary to have a reliable dose monitoring system. The in vitro experiments are used to determine the relative biological effectiveness (RBE) of liver and cancer cells in(More)
The electron shell structure of superheavy elements, i.e., elements with atomic number Z ≥ 104, is influenced by strong relativistic effects caused by the high Z. Early atomic calculations on element 112 (copernicium, Cn) and element 114 (flerovium, Fl) having closed and quasi-closed electron shell configurations of 6d(10)7s(2) and 6d(10)7s(2)7p1/2(2),(More)
A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115.(More)
Experimental investigations of transactinoide elements provide benchmark results for chemical theory and probe the predictive power of trends in the periodic table. So far, in gas-phase chemical reactions, simple inorganic compounds with the transactinoide in its highest oxidation state have been synthesized. Single-atom production rates, short half-lives,(More)
The fusion-evaporation reaction 244Pu(48Ca,3-4n){288,289}114 was studied at the new gas-filled recoil separator TASCA. Thirteen correlated decay chains were observed and assigned to the production and decay of {288,289}114. At a compound nucleus excitation energy of E{*}=39.8-43.9  MeV, the 4n evaporation channel cross section was 9.8{-3.1}{+3.9}  pb. At(More)
Standard wafer solar cells are made of near-semiconductor quality silicon. This high quality material makes up a significant part of the total costs of a solar module. Therefore, new concepts with less expensive so called solar grade silicon directly based on physiochemically upgraded metallurgical grade silicon are investigated. Metallurgical grade silicon(More)
M. Schädel, D. Ackermann, L.-L. Andersson, J. Ballof, M. Block, R.A. Buda, W. Brüchle, I. Dragojevi , Ch.E. Düllmann, J. Dvorak, K. Eberhardt, J. Even, J.M. Gates, J. Gerl, A. Gorshkov, P. Golubev, R. Graeger, K.E. Gregorich, E. Gromm, W. Hartmann, F.P. Heßberger, D . Hild, R. Hoischen, A. Hübner, E. Jäger, J. Khuyagbaatar, B. Kindler, I. Kojouharov, J.V.(More)
A. von Zweidorf1, R. Angert1, W. Brüchle1, S. Bürger2, K. Eberhardt2, R. Eichler1,3, H. Hummrich2, E. Jäger1, R. Jera2, H.-O. Kling2, J. V. Kratz2, U. Krille2, B. Kuczewski2, G. Langrock2, G. Lehr2, M. Mendel2, A. Nähler2, A. Peil2, V. Pershina1, U. Rieth2, M. Schädel1, B. Schausten1, E. Schimpf1, H.-J. Schött1, E. Stiel1, P. Thörle2, K. Tsukada4, N.(More)
We have measured the acceleration of neutrons by the material optical potential of solid 2H2. Using a gravitational spectrometer, we find a minimal kinetic energy Ec = (99+/-7) neV of neutrons from a superthermal ultracold neutron (UCN) source with solid 2H2 as an UCN converter. The result is in excellent agreement with theoretical predictions, Ec = 106 neV.
Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5)  MeV and half-life T_{1/2}=4.7(7)  μs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) (More)