1. ELBE Neutron Source IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 Klaus Seidel Technische Universität Dresden

2. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden ELBE at FZ Rossendorf Electron Linac for beams with high Brilliance and low Emittance Neutron laboratory of TUD with photon-neutron and D-T neutron sources

3. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden Deuteron beam: E d = 300 keV, I d = 10 mA on TiT target, continuous operation with up to 10 12 neutrons/s, pulsed operation (1 mA) 10  s …100  s with repetition rate of 1 Hz … 1 kHz. Electron beam: E e = 40 MeV, I e = 1mA on W target for bremsstrahlung and photo-neutron production  7·10 13 neutrons/s

4. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden Intension for fusion neutronics: production of high neutron fluxes with spectral distribution typical for fusion assemblies Example: flux spectrum in cells of the HCPB DEMO blanket (BBxxx, U. Fischer) Continuous part by the photo-neutron source with moderator and absorber, E e = 30 MeV Peak of fusion neutrons by the D-T generator IFMIF: Neutron energies above 15 MeV are of particular interest for assessing the data base.

5. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden Flux spectrum from the photo-neutron source at the maximum electron energy of E e = 40 MeV MCNPX model of the sourceFlux spectrum at sample position per one electron With I e = 1 mA the flux in the sample is 2.3·10 11 cm -2 ·s -1. The fluence of neutrons with E > 15 MeV applied during t irr = 10 h amounts to 1.04·10 12 cm -2.

6. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden Comparison with the parameters for the EFDA Task “Validation experiment of  -activities of Ta irradiated in fusion peak neutron spectrum” During t irr = 8.8 h a fluence of 7.9·10 11 cm -2 was applied and all  -activities that are important up to the recycling- limit of the material were measured with a HPGe- spectrometer and analysed with the European Activation System EASY (R.A. Forrest) EASY2005 calculation D-T neutrons Photo- neutrons Lu-176m Lu-177 Lu-178 Lu-178m Hf-180m Hf-181 Ta-178 Ta-178m (Ta-179) Ta-180 Ta-182 Ta-182m - (0.070) 32.2 16.7 7.61 1.48 - (0.086) 4.2·10 4 6.09 4.88 2.27 1.03 142. 79.5 244. 7.77 496 63.6 (33.2) 5.2·10 5 5.0·10 5 2.2·10 6 Specific activities [Bq/g] produced by

7. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden tested by the activity measurement Cross section data from EASY-2005

8. IAEA TC Meeting “Nuclear Data for IFMIF”, FZ Karlsruhe, October 4-6, 2005 K. Seidel, TU Dresden

16. Conclusions At the ELBE laboratory a photo-neutron source is under construction that will produce 7.1·10 13 neutrons/sec with energies ranging up to 30 MeV. For the neutron energy range 15 MeV < E < 30 MeV fluences of  10 12 neutrons/cm 2 can be applied in samples arranged close to the source. Ta was used - as an example of a typical heavy nucleus - to investigate the nuclear reactions that can be induced by these neutrons. With HPGe-spectroscopy the  -activities produced by the reactions (n,4n), (n,p), (n,d), (n,n’p), (n,  ), (n,n’  ), (n,2n  ), as well as (n,2n), (n,  ), can be measured, and the cross-section integrals obtained in this way, could be used for validating the evaluated data of the reactions in libraries.