Thin-target excitation functions, cross-sections and optimised thick-target yields for natMo(p,xn)(94g ,95m,95g,96(m + g))Tc nuclear reactions induced by protons from threshold up to 44 MeV. No Carrier Added radiochemical separation and quality control.

Production of 95mTc with proton bombardment of 95Mo

Alpha particle induced nuclear reactions were investigated with the stacked foil activation technique on natural niobium targets up to 43 MeV. Excitation functions were measured for the production of 96mgTc, 95mTc, 95gTc, 94gTc, 95mgNb and 92mNb. Cumulative cross-sections, thick target yields and activation functions were deduced and compared with available literature data. Applications of the excitation functions in the field of thin layer activation techniques and beam monitoring are also discussed.

Measurement and evaluation of the excitation functions for alpha particle induced nuclear reactions on niobium

Proton-rich Tc radionuclides have been identified as potential candidates for specific clinical and biological applications in the last decade. So far, these radionuclides have been produced either by proton-induced reaction on Mo targets or {alpha}-particle-induced reaction on Nb targets. This article lightens two heavy-ion-induced production routes of {sup 93,94,95,96}Tc radionuclides through {sup 7}Li+{sup nat}Zr and {sup 9}Be+{sup nat}Y reactions and provides important cross-sectional information in the projectile energy ranges 37-45 MeV and 30-48 MeV, respectively. Excitation functions of those reactions have been measured using the stacked-foil technique followed by the off-line {gamma}-spectrometric studies. Measured cross-sectional data have been interpreted comparing theoretical predictions of the two nuclear reaction model codes PACE-II and ALICE91. Experimental cross sections agreed with the theory. Measured production cross sections of {sup 94,95}Tc have been compared with those produced from the {alpha}+{sup 93}Nb reaction.

New routes for production of proton-rich Tc isotopes

Excitation functions of the reactions109Ag(3He,xn) and111Cd(p, xn) have been measured with stacked foil techniques for projectile energies E≦45 MeV and multiplicitiesx≦4 populating ground and spin isomeric states in112−x
In. Preequilibrium (PE) contributions are more pronounced for thep than for the3He entrance channel and for low multiplicitiesx and can be reproduced with the (geometry dependent) hybrid model. The observed isomeric cross section ratios require a reduced population for the high spin state (as compared with the expectation for equilibrated systems) whenever PE emission contributes significantly. Calculations for a full statistical model with a PE decay mode and approximate angular momentum conservation indicate PE neutron emission to be stretched in angular momentum space. For the (p, xn) reactions a more detailed coupling scheme is imperative whereas the (3He,xn) data suggest the competitive PE emission of complex particles.

Preequilibrium neutron emission in 109 Ag( 3 He, xn ) and 111 Cd( p, xn ) reactions

Excitation functions and isomer ratios in the reactions 93Nb(α, xn) (x = 1−4)

Isomer ratios in antimony and bromine fission fragments have been measured in the (12C+209Bi), ( alpha +204Pb) and (12C+196Pt) reactions, The values of the isomer ratios and their variation with energy are in accordance with the fragment angular momenta predicted by the Fermi gas model for the fissioning nucleus.

J.A.B. Goodall

Papers

Excitation functions and isomer ratios in the reactions 93Nb(α, xn) (x = 1−4)

Isomer ratios in fission fragments at high excitation

Spallation cross sections in the system 93Nb +4He