Program - Brookhaven National Laboratory

for extraction of very rare isotopes, needed for scientific experiments in nuclear astrophysics and basic
nuclear physics e.g. 148 Gd, 146 Sm and 154 Dy [1]. Due to the complexity of the involved nuclear reactions,
theoretical predictions of the radionuclide inventory are difficult and require benchmarking to improve
the models and calculation codes. Within the EC-funded projects HINDAS [2] and EUROTRANS (WP
NUDATRA) [3] essential progresses could be achieved concerning the development of codes and models, especially
TALYS and INCL4/ABLA, to get reliable nuclear data, in particular for the target materials such
as lead and bismuth. Experimental data from integral experiments for verification are urgently needed.
The here reported work is aimed to figure out an extensive chemical separation procedure to determine
quantitatively the target’s nuclide inventory and its radial and depth distribution. Due to the varying
proton fluxes at different positions in the target, a strong correlation to the production rates of radioisotopes
is expected. As a first step, a detailed gamma-analysis of multiple samples of positions with different
distances to the beam centre was carried out. After the dissolution in nitric acid, chemical separation
procedures for α- and long-lived β-emitting isotopes, e.g. 208/209/210 Po, 129 I and 36 Cl, were applied. First
results will be presented. The project is funded by the Swiss National Science Foundation (SNSF).
[1] D. Schumann, J. Neuhausen, J. Phys. G, 35 (2008) 014046. [2] Hindas Final Report, FIS5-00150. [3] Report
of the Numerical results from the Evaluation of the nuclear data sensitivities, FP-7 IP-EUROTRANS.
GE 4 2:40 PM
Online Production and Release Rates of Volatile Isotopes in a Pb/Bi Target Irradiated at
ISOLDE and Post-Irradiation Analysis
L. Zanini, E. Noah, European Spallation Source, P.O. Box 176, SE-22100 Lund, Sweden. M. Andersson,
K. Berg, V. Boutellier, R. Brütsch, J. Eikenberg. H. Franberg, D. Gavillet, F. Groeschel, E. Manfrin, J.
Neuhausen, D. Schumann, M. Wohlmuther, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland. J.
Krbanjevic, Ecole Polytechnique Fédérale de Lausanne, Centre de Recherches en Physique des Plasmas,
Lausanne, Switzerland. A. Grimberg, I. Leya, Physikalisches Institut, 3012 Bern, Switzerland. Y. Tall, S.
Cormon, M. Fallot, Y. Foucher, A. Guertin, T. Kirchner, SUBATECH Laboratory,
CNRS/IN2P3-EMN-Université, 44307 Nantes, France 2. U. Koester, Institut Laue-Langevin, 38042
Grenoble, France. H. Ravn, T. Stora, CERN, 1211 Geneva, Switzerland. J. C. David, S. Leray,
DSM/IRFU/SphN CEA Saclay, 91191 Gif-sur-Yvette, France.
For liquid metal spallation neutron targets it is crucial to know the composition and amount of volatile
radionuclides that are released from the target during operation. It is also important to know the total
amount produced, which can be possibly released in case of accident. One notable case is for Pb/Bi targets
(LBE) where different radionuclides can be produced, notably noble gases (Ar, Kr, Xe isotopes), and other
volatile isotopes such as Cd, Br, I, Hg, and Po. We reported previously on the results of an irradiation
experiment performed at ISOLDE on an LBE target [1]. The results were compared with predictions
from the latest versions of the FLUKA and MCNPX codes using different options for the intra-nuclear
cascades and evaporation/fission models. Subsequently, the irradiated target was transported to PSI and
examined. Investigations of both the tantalum target structure, and in particular the beam window, and
of the lead-bismuth eutectic, were performed using several experimental techniques. Concerning the leadbismuth,
mass spectrometry analysis indicated that the amount of noble gases is at the level of 0.1% of the
generated amount, in agreement with the expectations. The polonium content was measured with alpha
spectroscopy and results in good agreement with Monte Carlo calculations. In this paper we present the
final results from the different measurements, and discuss implications for spallation target design in light
of the strong interest in this material for Accelerator Driven Systems and for the European Spallation
Source.
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