Mitja Majerle for the “Energy Plus Transmutation” collaboration

 Subcritical reactor  Wider choice for reactor fuel ( 238 U, 232 Th)  Transmutation of nuclear waste  Increased safety  Accelerator  Protons or light ions of energy around 1 GeV  Very high powers (tens, hundreds of MeW)  Stability of the beam  Spallation reaction

 C.Rubbia at CERN (protons on lead block)  MUSE Cadarache (reactor k eff =0.95 with (d,t) source)  TRADE Casaccia (reactor coupled with cyclotron)  MEGAPIE at PSI (target research)

 Until today:  cross-section measurements on 660 MeV protons  Lead+parafine (GAMMA-2)  Lead target (PHASOTRON)  Energy Plus Transmutation  Lead in graphite block (GAMMA-MD)  Future:  Subcritical Assembly Dubna (SAD)

 Lead target MeV protons  Activation detectors (Au, Al, Bi)  129 I samples  Focus – spatial distribution of fast neutrons

 Lead target + nat U blanket  Protons (0.7-2 GeV), deuterons ( GeV)  Activation detectors (Al, Au, Bi, Cu, In, Ta, Y)  Solid state nuclear track detectors ( 235 U, 238 U, nat Pb)  Fast neutrons in uranium

 Lead target + graphite moderator  Deuterons 1.6 GeV  Activation detectors (Al, Au, Bi, Cu, In, Ta, Y)  Solid state nuclear track detectors ( 235 U, 238 U, nat Pb)  Fast neutrons in graphite

 Monoisotopic materials (Au, Al, Bi, In, Ta, Y, …)  Activation during the irradiation  (n,xn), (n,  ), (n,  ) reactions, but also (p,pxn),..  Activity measurement after the irradiation  Activity  number of produced isotopes n (n,xn), (n,  ), … HPGe detector 

 Irradiator material (Pb, 235 U, 238 U) + plastic, mica …  (n,f) reactions - fission fragments leave tracks in plastic  Chemical etching  Track counting with microscope  Tracks  number of fissions n n,fission tracks chemical etching

 MCNPX, FLUKA -> spectral fluence  Spallation  Transport of particles  Spectral fluence folded with cross-sections = number of produced isotopes or fissions -> experimental values  Experiment / calculations inside 30%:  Cross-sections or  Monte-Carlo codes ? by A. Potapenko

Phasotron experiment at 660 MeV : measurement/FLUKA calculation. Detectors are placed on top of the target along its length. Energy plus transmutation at 1.5 GeV: Measurement / MCNPX calculation. Detectors are placed in radial direction In the first gap.

 (n,xn) reaction in energy range MeV  Materials in detectors: Al, Au, Bi, Cu, In, Ta, Y  Other : 127 I, 129 I  Higher x reactions – n,3n-n,10n – few measurements  (n,f) reactions in energy range MeV  Materials : Pb, 235 U, 238 U  Other heavy materials : Au, W, Bi, Th  For materials other than U few measurements

 Monte-Carlo predictions of XADS within 30% with the experiment –better accuracy needed for real ADS  Mostly (n,xn) and (n,f) cross-sections in energy range MeV are needed  Cross-sections that we need can be used also for monitoring neutron fluxes at other experiments, in reactors...  Currently we work on some measurements inside EFNUDAT (Ondrej Svoboda talk)