Cryomodule Test Bunker for the ILC Technology Network

\n"ILC Technology Network" (ITN) is an international framework for the technological development outlined in the time-critical Work Package (WP). The focus of WP1 and 2 are cavity production and cryomodule design, respectively. The High Energy Accelerator Research Organization known as KEK plans to produce one cryomodule equipped with eight superconducting 9-cell cavities for WP1 and 2 from FY2023 and conduct measurements by FY2027. To do that, a test facility will be required to perform the measurements. This test facility was named "Cryomodule Test Bunker" (CTB). The refrigerator (Linde LR280) currently operating at KEK will be used for CTB. The helium transfer line has been designed based on KEKB’s transport line design; however, it was slightly modified because the International Linear Collider (ILC) does not use liquefied nitrogen for the thermal radiation shield. It is planned to install a 2K refrigerator, a purification filter, etc. The construction of the CTB will enable us to measure the performance of the cryomodules which are the main components of the ILC. This indicates that it will be possible to verify various aspects of the fabrication and inspection of cryomodules for the ILC, and is a very important technological step towards the construction of the ILC. It can also be used as a general-purpose test stand for superconducting accelerators, which will be useful in developing future superconducting accelerators.\n