A systematic investigation of (n,t) reactions at 14–15 MeV on medium and heavy mass nuclei

Ground-state and isomeric-state cross-sections for 92Mo(n,α)89Zr and 95Mo(n,p)95Nb reactions in the 13–15 MeV energy region

The (n,α) and (n,p) cross-sections and their isomeric ratios (σ m /σ g ) were measured at 13–15 MeV for 92Mo and 95Mo by activation and off-line γ-ray spectrometry. The activated Mo samples combined with Al foils were used to obtain the cross-section values and the neutron flux, generated using the 3H(d,n)4He reaction. The cross-sections of the ground states were obtained using the metastable state absolute cross-sections and the residual nuclear decay rule. The excitation functions, total cross-sections, and isomeric ratios for the 92Mo(n,α)89m,gZr and 95Mo(n,p)95m,gNb reactions were calculated using the TALYS-1.95 software. 92Mo(n,α)89m + gZr and 95Mo(n,p)95m + gNb reaction excitation functions were obtained using the EMPIRE-3.2.3 package. These simulation results were compared with the corresponding experimental data and with the evaluated data from the ENDF/B-VIII.0, JEFF-3.3, CENDL-3, and ROSFOND libraries. Only partial agreements were observed.

Cross section measurements for gallium in the neutron energy range of 13.5 to 14.8MeV

Cross sections for (n,2n), (n,p) and (n,n´α) reactions have been measured on gallium isotopes at the neutron energies of 13.5–14.8 MeV using the activation technique. The monoenergetic neutron beam was producedviathe3H(d,n)4He reaction. The neutron fluences were determined using the monitor reaction27Al(n,α)24Na. The activities induced in the reaction products were measured using high-resolution gamma-ray spectrometry. Data are reported for the following reactions:69Ga(n,2n)68Ga,71Ga(n,2n)70Ga,69Ga(n,p)69mZn,71Ga(n,p)71mZn and71Ga(n,n´α)67Cu. Nuclear model calculations using the code HFTT, which employs the Hauser–Feshbach (statistical model) and exciton model (precompound effects) formalisms, were undertaken to describe the formation of the reaction products. Results are discussed and compared with some corresponding values found in the literature, with some established systematics and with the evaluated data given in ENDF/B-VII.0, CENDL-3.1 and JENDL-4.0.

Influence of reaction channel on the isomeric cross-section ratio

The influence of reaction channel on the isomeric cross-section ratio was investigated by analysing the experimental data on the reactions 52Cr(p, n)52m,gMn, 52Cr(3He, t)52m,gMn, 54Fe(d, α)52m,gMn, 54Fe(n, t)52m,gMn and 54Fe(3He, α p)52m,gMn over the incident particle energy range extending up to 35 MeV. The influence is most pronounced when the channels differ widely, for example (p, n) and (3He, t) processes, i.e. when the reaction mechanisms are different. The nuclear model calculational code EMPIRE-II described the isomeric cross-section ratio rather well in the case of a simple nucleon emission reaction, but not when complex reaction channels were involved.

Measurement of fission neutron spectrum averaged cross sections of some threshold reactions on dysprosium: small-scale production of no-carrier-added153Gd in a nuclear reactor

Employing the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy fission neutron spectrum averaged cross sections were measured for several (n, 2n), (n,p) and (n, α) reactions on isotopes of dysprosium; our measurements constitute the first systematic studies. Of special interest was the investigation of the156Dy(n, α)153Gd reaction for the production of no-carrier-added153Gd in a nuclear reactor. Using 100% enriched156Dy target, 8633 KBq of153Gd per batch can be produced which is, however, not sufficient for medical application.

Measurement of fission neutron spectrum averaged cross sections of some threshold reactions on europium: small scale production of no-carrier-added153Sm in a nuclear reactor

Employing the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy fission neutron spectrum averaged cross sections were measured for several (n, 2n), (n, p) and (n, α) reactions on isotopes of europium. Our measurements constitute the first systematic studies. Of special interest was the investigation of153Eu(n, p)153Sm reaction for the production of no-carrier-added153Sm in a nuclear reactor. Using 100% enriched153Eu target, 97.21 MBq153Sm per batch can be produced which is, however, not sufficient for medical application.

Fission neutron spectrum averaged cross sections of some threshold reactions on cadmium: production feasibility of no-carrier-added 103Pd in a nuclear reactor

Systematic studies on fission neutron spectrum averaged cross sections of some threshold reactions like (n,p) and (n,α) on cadmium were carried out using the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy. Special attention was paid to the formation of 103Pd via the 106Cd(n,α) 103Pd reaction since it is an important therapeutic radionuclide. At a fast flux neutron density of 7.5 × 1013 cm2s-1 and an irradiation time of 120 h, using 100% enriched 106Cd target 340 MBq of no-carrier-added 103Pd per batch could be produced. The method is thus suitable for medium-scale production of this radionuclide.

Measurement of fission neutron spectrum averaged cross sections of some threshold reactions on zirconium: Production possibility of no-carrier-added 90Y in a nuclear reactor

Employing the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy fission neutron spectrum averaged cross sections were measured for several (n, p) and (n, α) reactions on isotopes of zirconium; our measurements constitute the first systematic study. The special interest was in the investigation of the 90Zr(n, p)90Y reaction for the production of no-carrier-added 90Y in a nuclear reactor. At a fast neutron flux density of 7.5 × 1013 cm−2 s−1 and an irradiation time of 120 h, using 100% enriched 90Zr target 0.548 GBq of no-carrier-added 90Y per batch could be produced. The method is thus suitable for medium-scale production of this radionuclide.

Fission neutron spectrum averaged cross sections of some threshold reactions on titanium: production feasibility of 45Ti in a nuclear reactor

Systematic studies on fission neutron spectrum averaged cross sections of some threshold reactions like (n, 2n), (n, p) and (n, α) on titanium were carried out using the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy. Special attention was paid to the formation 45Ti via the 46Ti(n, 2n)45Ti reaction since 45Ti labeled compounds are potentially important radiopharmaceuticals. At a fast flux neutron density of 7.5 × 1013 cm−2 s−1 and using 100% enriched 46Ti target, 8.58 MBq saturation activity of 45Ti per batch can be produced. Due to rather low activity and low specific activity the procedure is not feasible from medical application point of view.