Cross sections and calculated yields of some radionuclides of yttrium, strontium and rubidium formed in proton-induced reactions on enriched strontium-86: possibility of production of 85gSr, 83Rb and 82mRb in no-carrier-added form

Cross sections of the 86Sr(p,3n)84mY, 86Sr(p,αn)82mRb, and 86Sr(p,x)85gSr reactions were measured from their respective thresholds up to 16.2 MeV and from 23.0 to 44.1 MeV at FZJ, and from 14.3 to 24.5 MeV at LBNL, using 96.4% enriched 86SrCO3 as target material. Thin targets prepared by sedimentation were irradiated with protons in a stacked-form, and the induced radioactivity was measured by high-resolution γ-ray spectrometry. Nuclear model calculations based on the code TALYS reproduced our experimental cross section data well. From the excitation functions, the integral yields of the above three radionuclides were calculated. The yield of 85gSr via the natSr(n,γ) process was also measured using the TRIGA Mark-II reactor at AERE, Savar. A comparison of the reactor and cyclotron production of carrier-added 85gSr is given. The production possibilities of the three investigated radionuclides in no-carrier-added forms at a 30 MeV cyclotron via new routes are discussed.

Ion beam activation of natCu, natTi, natNi and measurement of product formation cross sections at low energy (<10 MeV)

In this study we investigated the production cross sections of natCu(p, x)63,65Zn, natTi(p, x)48V, natNi(p, x)55Co,61Cu and natCu(α, x)66,67,68Ga, natTi(α, x)49,51Cr, natNi(α, x)63,65Zn reactions in the low energy range using the foil activation technique. The samples were activated in vacuum at 5 MV tandem (Pelletron) accelerator installed at National Centre for Physics (NCP), Islamabad, Pakistan. The reaction products were identified with the help of off-line gamma ray spectroscopy system connected with Genie 2000 software. The data analysis revealed the production of different radioisotopes that have valuable importance in monitoring charged-particle beams and medical applications. The measured results were verified by comparing them with earlier evaluated data as well as with the theoretical values given in the TENDL-library based on TALYS-1.9 code calculations.

The role of chemistry in accelerator-based production and separation of radionuclides as basis for radiolabelled compounds for medical applications

Radiochemical separations used in large scale routine production of diagnostic and therapeutic radionuclides at a particle accelerator for patient care are briefly outlined. The role of chemistry at various stages of development of a production route of a novel radionuclide, namely nuclear data measurement, high-current targetry, chemical processing and quality control of the product, is discussed in detail. Special attention is paid to production of non-standard positron emitters (e.g. 44gSc, 64Cu, 68Ga, etc.) at a cyclotron and novel therapeutic radionuclides (e.g. 67Cu, 225Ac, etc.) at an accelerator. Some typical examples of radiochemical methods involved are presented.

An overview of activation cross-section measurements of some neutron and charged-particle induced reactions in Bangladesh

Over the last several decades, our research group has been working on nuclear data measurements using a J-25 Neutron Generator, a TRIGA Mark II Research Reactor and a Tandem Accelerator at Savar, as well as an Am/Be neutron source at Rajshahi. The spectrum of fast neutrons having energies from 0.5 to 20 MeV in the core of the TRIGA reactor as well as from 1.5 to 11 MeV of the Am/Be source was well characterized for validation of evaluated data of neutron threshold reactions. Spectrum-averaged cross sections were determined by integral measurements. The integral values measured at both the reactor and the Am/Be source were compared with the integrated data deduced from measured and evaluated excitation functions of some nuclear reactions given in some data libraries. As example, the details on the integral and integrated cross sections of the 64Zn(n,p)64Cu and 60Ni(n,p)60Co reactions are discussed. In both cases, integral test shows that further improvement of the evaluated excitation function reported in data libraries is needed. The use of a newly developed facility at the 3 MV Tandem Accelerator in measurement of proton induced reaction cross sections in the energy region below 5 MeV is outlined, and new results on the 64Ni(p,n)64Cu and natNi(p,x)61Cu processes below 3 MeV are discussed.

An overview of nuclear data standardisation work for accelerator-based production of medical radionuclides in Pakistan

The standardisation of nuclear reaction cross section data is an integral part of optimisation of production routes of medical radionuclides. The production cross sections are available for the reactor and cyclotron produced radionuclides to be used for diagnostics or therapeutic procedures. The types of nuclear data needed, and the sources of their availability are summarized. The method of standardisation of charged-particle data is briefly described. A historical overview of research work in Pakistan in this direction is given. Examples of a few medically important radionuclides, such as 64Cu, 86Y, 89Zr, 103Pd, 186Re, etc., whose data were standardised and evaluated are highlighted. Calculated thick target yields from the recommended data are given. Some new directions in the nuclear data research are outlined.

Positron Emission Intensity in the Decay of 86gY for Use in Dosimetry Studies

The β⁺-emitting radionuclide ^86gY (t_1/2 = 14.7 h) forms a matched-pair with the β⁻-emitting therapeutic radionuclide ⁹⁰Y (t_1/2 = 2.7 d) for theranostic application in medicine. This approach demands a precise knowledge of the positron emission probability of the PET nuclide which was until recently rather uncertain for ^86gY. In this work, an ^86gY source of high radionuclidic purity was prepared and a direct measurement of the positron emission intensity per 100 decay of the parent (hereafter “positron emission intensity”) was performed using high-resolution HPGe detector γ-ray spectroscopy. The electron capture intensity was also determined as an additional check by measuring the K_α and K_β X-rays of energies 14.1 and 15.8 keV, respectively, using a low energy HPGe detector. From those measurements, normalized values of 27.2 ± 2.0% for β⁺-emission and 72.8 ± 2.0% for EC were obtained. These results are in excellent agreement with values recently reported in the literature based on a detailed decay scheme study.