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Neutron induced reaction cross-section measurements display special interest both for fundamental research in the Nuclear Physics field and many practical applications. The Institute of Nuclear and Particle Physics (INP) of the National Centre for Scientific Research Demokritos (N.C.S.R. "D") hosts the 5.5 MV T11/25 Van de Graaff accelerator, which is the only accelerator used in Greece for research purposes. This accelerator recently underwent a major upgrade, including the installation of a new pelletron charging system, two new ion sources, a new gas stripper and beam optics. This neutron facility can produce quasi-monoenrgetic neutron beams in the energy range ∼16-19 MeV via the 3 H(d,n)4 He (D-T) reaction, employing a tritiated Titanium target (TiT). The neutron induced cross sections of a total of nine reaction channels have been experimentally measured in the present work, via the activation technique, using enriched Ge targets. These targets produce more accurate cross-section results, in comparison with the - most commonly used in bibliography - nat Ge samples, since they do not suffer from contaminating reactions that produce the same residual nucleus. Monte Carlo simulations were also performed via the combined use of MCNP5 and NeuSDesc codes for the simulation of the neutron beam. [ABSTRACT FROM AUTHOR]

Nine neutron induced reactions on Ge isotopes (70Ge(n,2n)69Ge, 76Ge(n,2n)75Ge, 73Ge(n,p)73Ga, 72Ge(n,p)72Ga, 73Ge(n,d/np)72Ga, 74Ge(n,d/np)73Ga, 74Ge(n,α)71mZn, 72Ge(n,α)69mZn, 73Ge(n,nα)69mZn) have been measured in this work at energies 16.4-18.9 MeV. For these reactions, most of the experimental datasets in literature were obtained with a natGe target. However, the residual nucleus produced by some reaction channels can also be produced from neighboring isotopes, acting as a contamination for the measured reactions. This contribution must be subtracted, based on theoretical calculations, bearing their own uncertainties. The use of enriched targets however, does not suffer from such contaminations, leading to accurate experimental results. In this scope, five highly isotopically enriched Ge samples have been used in this work. The quasi-monoenergetic neutron beams were produced via the 3H(d,n)4He reaction at the 5.5 MV Tandem Van de Graaff accelerator of N.C.S.R. 'Demokritos'. The cross section of these nine reactions were measured using the activation method, with respect to the 27Al(n,α)24Na reference reaction. [ABSTRACT FROM AUTHOR]