Bianchi Antonio, Venturini Delsolaro Walter
CERN, Geneva, Switzerland.
INFN, Milano, Italy.
Sci Rep. 2023 Oct 10;13(1):17075. doi: 10.1038/s41598-023-44021-w.
Since the late '80s, CERN has pioneered the development of niobium thin film radio-frequency (RF) cavities deposited on copper substrates for several particle accelerator applications. However, niobium thin film cavities historically feature a progressive performance degradation as the accelerating field increases. In this study, we describe a temperature mapping system based on contact thermometry, specially designed to obtain temperature maps of niobium-coated copper cavities and, consequently, study the mechanisms responsible for performance degradation. The first temperature maps on a niobium/copper 1.3 GHz cavity are reported along with its RF performance. In addition to some hotspots displayed in the temperature maps, we surprisingly observed a temperature decrease in a limited portion of the cavity cell as the accelerating field increased. This may shed new light on understanding the heat dissipation of niobium thin film cavities in liquid helium-I, which might be exploited to improve the RF cavity performance.
自20世纪80年代末以来，欧洲核子研究组织（CERN）率先开发了用于多种粒子加速器应用的、沉积在铜基板上的铌薄膜射频（RF）腔。然而，从历史上看，随着加速场的增加，铌薄膜腔的性能会逐渐退化。在本研究中，我们描述了一种基于接触式测温法的温度测绘系统，该系统经过专门设计，用于获取铌涂层铜腔的温度分布图，并因此研究导致性能退化的机制。报告了铌/铜1.3 GHz腔的首批温度分布图及其射频性能。除了温度分布图中显示的一些热点外，我们还意外地观察到，随着加速场的增加，腔单元的有限部分温度下降。这可能为理解铌薄膜腔在液氦-I中的散热情况提供新的线索，有望借此提高射频腔的性能。
