Elaboration and characterization of hydrogen standard stable under heavy ion irradiation: Application to nuclear astrophysics

A hydrogen standard has been carried out by ion implantation in silicon. The silicon wafer was implanted with hydrogen at different energies and fluences to provide a ∼100 nm flat distribution to the specimen. The samples obtained were characterized by mean of elastic recoil detection analysis (ERDA) and resonant nuclear reaction analysis (RNRA). All important properties of the hydrogen standard have been controlled: isotopic purity, depth profile, stability under ion irradiation and reproducibility. The standards were validated by the measurement of the resonant cross-section of the 13C(p,γ)14N reaction. The similarity of the resonance energy, the resonance width and the resonance strength measurements with those reported in literature confirms the validity of the proposed procedure for hydrogen standards. Therefore, this kind of target could be used to investigate all nuclear reactions in which a proton is involved, from reactions with astrophysical interest to the ones with concern in material analysis.