Excitation functions of threshold reactions on 45Sc and 55Mn induced by 6 to 13 MeV neutrons

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 sections of 56Fe(n, p)56Mn, 55Mn(n, p)55Cr, 52Cr(n, p)52V, 56Fe(n, α)53Cr, 55Mn(n, α)52V and 52Cr(n, α)49Ti reactions using phenomenological level density models from threshold to 20 MeV

⁵⁶Fe(n,p)⁵⁶Mn, ⁵⁵Mn(n,p)⁵⁵Cr, ⁵²Cr(n,p)⁵²V, ⁵⁶Fe(n, α)⁵³Cr, ⁵⁵Mn(n, α)⁵²V and ⁵²Cr(n, α)⁴⁹Ti reactions are evaluated using four phenomenological nuclear level density models from reaction threshold to 20 MeV. The calculated data is compared with the experimental nuclear reaction data from EXFOR database. Statistical factors H, D and R are computed to identify the best fit. Level density parameters are adjusted for further improvement of the fitting. Back shifted Farmi-gas model gives a resemblance of neutron-induced ⁵⁶Fe, ⁵⁵Mn and constant temperature Fermi-gas model gives a closeness for ⁵²Cr reaction with our new parameter values.

Measurement of 14.54 MeV neutron induced reaction cross sections of Cr and Mn with covariance analysis

The 50Cr(n,2n)49Cr, 52Cr(n,2n)51Cr, 52Cr(n,p)52V, 55Mn(n,2n)54Mn, 55Mn(n,α)52V and 55Mn(n,γ)56Mn reaction cross sections at the neutron energy of 14.54 ± 0.24 MeV were measured by using activation method along with off-line γ-ray spectrometry. The 27Al(n,p)27Mg monitor reaction was used for the 52Cr(n,p)52V and 55Mn(n,α)52V reactions, whereas the 197Au(n,γ)198Au monitor reaction for the 55Mn(n,γ)56Mn reaction. The 27Al(n,α)24Na monitor reaction was used for other three reactions. The neutron beam was generated from the T(d,n)4He reaction using the Purnima neutron generator at BARC, Mumbai. The covariance analysis for the uncertainties of reaction cross sections was performed by considering the correlations between different attributes. The present results were compared with the literature data, evaluated data of ENDF, ROSFOND, CENDL, JENDL and JEFF libraries as well as with the theoretical values based on TALYS-1.9 calculation.

Measurement of cross sections and isomeric cross-section ratios for the (n,2n) reactions on 85,87Rb in energies between 13 and 15 MeV

The (n,2n) cross sections and their isomeric cross-section ratios (σm/σg) in the neutron energy range 13–15 MeV have been measured for 85,87Rb by an activation and off-line γ-ray spectrometric technique using the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The natural Rb samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The neutrons were produced via the 3H(d,n)4He reaction. The pure cross section of the ground-state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. The 85Rb(n,2n)84m,gRb and 87Rb(n,2n)86m,gRb reaction excitation functions and their isomeric cross-section ratios were also calculated theoretically using the TALYS-1.8 code with different level density options. Results are discussed and compared with the corresponding literature data.

Measurements of activation cross sections by cyclic activation method for (n,2n) reaction on 144Sm isotope around 14 MeV neutron energy

Measurement of activation cross sections for the 144Sm(n,2n)143gSm reaction was performed by Cyclic Activation Method (CAM) around 14 MeV neutron energy. Natural samarium samples were irradiated by the neutrons produced by 3H(2H,n)4He reaction using a neutron generator. Delayed γ ray activities produced by fast neutrons in samples were measured by a high resolution γ ray spectrometer [high-purity Germanium (HpGe) detector]. The measured cross sections are compared with the results of model calculation (STAPRE code) and evaluated data (JEFF 3.0/A).

Measurement and covariance analysis of 59Co(n, 2n)58Co reaction cross sections at the effective neutron energies of 11.98 and 15.75 MeV

The 59Co(n, 2n)58Co reaction cross sections relative to the cross sections of the 115In(n, n′)115mIn reaction have been measured at the effective neutron energies of 11.98 and 15.75 MeV by using activation and off-line γ-ray spectrometric technique. Neutron beam used in the present experiment was generated from the 7Li(p, n)7Be reaction with the proton energies of 14 and 18 MeV at the 14UD BARC-TIFR Pelletron facility, Mumbai. We also present the covariance information by taking into account the sources of error and the correlations between the attributes influencing the measurements. The 59Co(n, 2n)58Co reaction cross sections from the present work are then compared with the values from different evaluated nuclear data libraries. The micro-correlation technique suggested by Smith was modified to generate the covariance matrix for the measurements of reaction cross sections as the efficiencies of detector for the sample and monitor are correlated.

Scandium(iii) complexes of monophosphorus acid DOTA analogues: a thermodynamic and radiolabelling study with 44Sc from cyclotron and from a 44Ti/44Sc generator

The influence of the phosphonic/phosphinic acid pendant arm in DOTA derivatives on properties of their Sc³⁺ complexes and efficiency of their ⁴⁴Sc labelling were investigated.

Excitation functions of nuclear reactions leading to the soft-radiation emitting radionuclides45Ca,49V and204Tl in beam collimator materials used in proton therapy

Summary. Cross sections of nuclear reactions leading to the formation of the soft-radiation emitting radionuclides45Ca (T1/2=163 d; β−=260 keV),49V (T1/2=330 d;Kα=4.51 keV) and204Tl (T1/2=3.78 a; β−=763 keV) in proton induced reactions on titanium and lead, respectively, often used as collimators in proton therapy facilities, were measured for the first time over the energy range extending up to 200 MeV. Use was made of the stacked-foil technique. Elaborate radiochemical separations were performed and the radioactivity of the products was determinedviaanticoincidence beta counting, liquid scintillation counting or X-ray spectrometry. The experimental data were compared with the results of nuclear model calculations using the codes ALICE-IPPE and TALYS. In general good agreement was obtained. In the case of204Tl, however, the calculated values from ALICE-IPPE in the energy region above 80 MeV deviated considerably from the experimental data, possibly due to strong contributions of multiple particle emission reactions.

Activation cross-sections for (158)Dy(n,p)(158)Tb, (156)Dy(n,alpha)(153)Gd and (160)Dy(n,p)(160)Tb reactions induced by neutrons at 14.7MeV

The cross-sections for the (158)Dy(n,p)(158)Tb, (156)Dy(n,alpha)(153)Gd and (160)Dy(n,p)(160)Tb reactions induced by 14.7MeV neutrons were measured in this work and calculated by a previously developed formula. Measurements were corrected for gamma-ray attenuations, random coincidence (pile-up), dead time and fluctuation of neutron flux. 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 products.