0105624 - UJF-V 20043193 RIV NL eng J - Journal Article
Karamian, S. A. - Carroll, J. J. - Adam, Jindřich - Demekhina, NA.
Production of the Hf-178m2 isomer using a 4.5-GeV electron accelerator.
[Produkce izomeru Hf-178m2 pomocí 4.5 GeV elektronového urychlovače.]
Nuclear Instruments & Methods in Physics Research Section A. Roč. 530, č. 3 (2004), s. 463-472. ISSN 0168-9002. E-ISSN 1872-9576
R&D Projects: GA AV ČR KSK1048102
Keywords : electron beam * bremsstrahlung * 4,5 GeV
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders
Impact factor: 1.349, year: 2004

High-productivity methods are required for the accumulation of long-lived isomers in amounts that are sufficient for the creation of experimental targets. A tantalum sample was activated with the Yerevan synchrotron using 4.5-GeV bremsstrahlung and the presence of Hf-178m2 was detected with good statistical accuracy by gamma-activity measurements. The integrated and mean cross-section values were deduced from the experiment. The isomer-to-ground-state ratio was then estimated and compared with that known for the p + Ta reaction studied at 660 MeV. In the present experiment, both converter and target were relatively thin for better definition of the experimental conditions. However, an assembly designed for high-productivity irradiations should be thick and then the converter can also serve as the target sample when irradiated with a high-energy electron beam. The optimization of the isomer production was solved analytically and the largest estimated yield was determined as calibrated to the experimental yield. The maximum yield of Hf178-2 was found to be of about 3 x 10(9) nuclei/s using an electron beam current of 100 muA. This is lower than the yield achieved with proton beams, although for a practical comparison the total cost and radiation safety conditions should be considered. The present results provide a basis for numerical estimations.

Vzorek tantalu aktivován jerevanským urychlovačem s využitím brzdného záření 4.5 GeV. Přítomnost Hf-178m2 detektována s dobrou statistickou přesností pomocí gama aktivačních měření.
Permanent Link: http://hdl.handle.net/11104/0012856