• Glock, H. - W.; Knobloch, J.; Neumann, A.; Vélez-Saiz, A.: Industrial X-Ray Tomographie as a Tool for Shape and Integrity Control of SRF Cavities. In: Kenji Saito ... [Ed.] : SRF2021 - Proceedings of the 20th International Conference on RF SuperconductivityGeneva: JACoW, 2022. - ISBN 978-3-95450-233-2, p. THOTEV07/1-8
    https://srf2021.vrws.de/papers/thotev07.pdf

Open Access Version

Abstract:
Industrial X-ray tomography offers the possibility to capture the entire inner and outer shape of a superconducting radio frequency (SRF) cavity, providing also insights in weld quality and material defects. As a non-contact method this is especially attractive to investigate shape properties of fully processed and closed cavities. A drawback is the inherently strong X-ray damping of niobium, which causes the demand for intense hard X-rays, typically beyond the capabilities of dc-Xray- tubes. This also limits the accuracy of material borders found by the tomographic inversion. To illustrate both capabilities and limitations, results of X-ray tomography investigations using three different cavities are reported, also describing the fundamental parameters and the hard- and software demands of the technology. We also discuss the non-trivial transferring of tomography data into RF simulation tools.