Speaker
Description
Development and testing of nanostructured uranium carbide targets for ISOLDE physics
Authors: V. Berlin$^1$, M. Au$^1$, E. Aubert$^1$, A. Boucherie$^1$, N. Conan$^1$, B. Crepieux$^1$, A. Dorsival$^1$, M.A. Grasser$^1$, L. Lambert$^1$, E. Reis$^1$$^,$$^2$, S. Rothe$^1$, S. Stegemann$^1$, J. Vollaire$^1$, S. Usta$^1$, J. Zucchi$^1$
$^1$ Center for European Nuclear Research, Geneva, Switzerland
$^2$ Institute for Materials Science and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Essen, Germany
The intensity of a radioactive ion beam at CERN-ISOLDE depends on multiple factors, including the primary beam intensity, target thickness, production cross-section for specific isotopes, as well as the efficiency of isotope extraction, ionization, and purification. To allow for a reasonably fast release of the produced nuclei, the target should be tailored to optimize these parameters by selecting target materials that are chemically and thermally stable under operational conditions and facilitate rapid diffusion and effusion rates of the elements of interest [1].
Uranium carbide (UC$_x$) targets represent the majority of targets routinely employed at ISOLDE, accounting for nearly 60% of the total usage in recent years. Carbide materials are particularly attractive for the production of challenging radioactive ion beams (RIBs), as their chemical inertness and high thermal stability facilitate the extraction of refractory isotopes that are otherwise difficult to obtain. Given these favourable properties and encouraged by significant performance gains observed with other sub-micron and nanostructured materials tested at ISOLDE (e.g., Y$_2$O$_3$, SiC, CaO), the development of nanostructured UC$_x$ has become a priority for the ISOLDE community.
In this work, we will present the outcome of the ISOLDE Type A laboratories’ commissioning programme, as well as first experiences of producing nanostructured UC$_x$ targets in the Nanolab. We will also report on results from the latest online testing campaign, evaluating the performance of nano-UC$_x$ targets against conventional UC$_x$ targets and earlier nanostructured UC$_x$ materials produced within the ActILab project [2–4].
References:
- J.P. Ramos, "Thick solid targets for the production and online release of radioisotopes: The importance of the material characteristics – A review", Nucl. Instrum. Meth. B 463 (2020) 201–210.
- ENSAR ActILab Collaboration. 3rd and final reporting for actilab, 2014.
- A. Andrighetto, P. Bricault, R. Catherall, P. Delahaye, S. Essabaa, H. Franberg- Delahaye, A. Gottberg, I. Guenther-Leopold, P. Kunz, C. Lau, B Roussiere, M.G. Saint-Laurent, T. Stora, L. Tecchio. “UCx prototype target tests for ActiLab-ENSAR”, Technical report, CERN, Geneva, 2012.
- A. Gottberg, “Target materials for exotic ISOL beams”, Nucl. Instrum. Meth. B 376 (2016) 8–15.