Fermilab’s 1.3 GHz prototype cryomodule for the Linac Coherent Light Source Upgrade (LCLS-II) has been tested at Fermilab’s Cryomodule Test Facility (CMTF). Aspects of the cryomodule design have been studied and tested. The cooldown circuit was used to quickly cool the cavities through the transition temperature, and a heater on the circuit was used to heat incoming helium for warmup. Due to the 0.5% slope of the cryomodule, the liquid level is not constant along the length of the cryomodule. This slope as well as the pressure profile caused liquid level management to be a challenge. The microphonics levels in the cryomodule were studied and efforts were made to reduce them throughout testing. Some of the design approaches and studies performed on these aspects will be presented. Fermilab is operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359 with the United States Department of Energy. This work was supported, in part, by the LCLS-II Project.

New linear superconducting accelerators need superconducting magnet packages installed inside SCRF cryomodules to focus and steer electron or proton beams. A superconducting magnet package was designed and built as a collaborative effort of FNAL and KEK. The magnet package includes one quadrupole and two dipole windings. It has a splittable in the vertical plane configuration and features for conduction cooling. The magnet was successfully tested at room temperature, in a liquid He bath, and in a conduction cooling experiment. This paper describes the design and test results, including magnet cooling, training, and magnetic measurements by rotational coils. The effects of superconductor and iron yoke magnetization, hysteresis, and fringe fields are discussed.

New Linear Accelerators based on superconducting radiofrequency (SCRF) cavities need compact and efficient superconducting magnet packages to focus and steer electron or proton beams. These magnets should be combined with SCRF cryomodules and installed inside or between them. A recent activity in this area was directed by FNAL-KEK collaboration to splittable conduction cooled magnets. Several magnet prototypes were built and successfully tested. These magnets were designed for high energy beams used in ILC, and Project-X. Nevertheless, there is an interest to explore splittable conduction cooled magnets for new accelerators: FNAL ASTA and PIP-II, KEK STF, SLAC LCLS II. The paper describes a conceptual design of splittable conduction cooled superconducting magnet which could be mounted inside SCRF cryomodule. The magnet package combines the quadrupole magnet and dipole correctors. The presented magnetic design confirms the specified magnet package parameters.

A superconducting solenoid-based focusing lens was designed and built for use in the SSR1 cryomodule of PXIE test facility at FNAL. As the cryomodule contains superconducting spoke-type cavities, one of main goals during design stage was minimization of magnetic field on walls of the cavities. The design also attempted minimization of the uncertainty of the magnetic axis position in the lens. This report describes main features of the design and summarizes results of performance tests and magnetic axis position measurements.

Superconducting spoke resonators (SSR1 and SSR2) envisioned for Project X will be developed in Fermilab and operated at temperatures down to 2 K in continuous wave (CW) mode. Each spoke cavity will be tested individually in a cryostat that replicates conditions in the longer multi-cavity cryomodules. This test cryostat has all the features of the longer cryomodules – magnetic shielding, 80 K thermal shield, multi-layer insulation, support post, and input coupler [1]. Fermilab is in the processing of retrofitting the existing test cryostat which was originally designed for operation at 4.5 K. This paper describes the design of the conversion of the current test cryostat, flexible transfer lines, helium relief system and cryogenics interface.

A new superconducting quadrupole magnet for linear accelerators was fabricated at Fermilab. The magnet is designed to work inside a cryomodule in the space between SCRF cavities. SCRF cavities must be installed inside a very clean room adding issues to the magnet design, and fabrication. The designed magnet has a splittable along the vertical plane configuration and could be installed outside of the clean room around the beam pipe previously connected to neighboring cavities. For more convenient assembly and replacement a "superferric" magnet configuration with four racetrack type coils was chosen. The magnet does not have a helium vessel and is conductively cooled from the cryomodule LHe supply pipe and a helium gas return pipe. The quadrupole generates 36 T integrated magnetic field gradient, has 600 mm effective length, and the peak gradient is 54 T/m. In this paper the quadrupole magnetic, mechanical, and thermal designs are presented, along with the magnet fabrication overview and first test results.

In an attempt to demonstrate an average accelerating gradient of 31.5 MV/m as in the design of the ILC, the S1-Global project [1] is a cryomodule being constructed by an international collaboration hosted by KEK and including INFN, FNAL, DESY and SLAC. The S1Global system joins two half-length cryomodules, each 6 m in length and containing 4 cavities, Module-C contains cavities from FNAL and DESY and was constructed by INFN. Module-A contains four KEK cavities and was constructed by KEK. The assembly of the cryomodules started in January 2010, and was just completed in May. In this paper, construction experience of the S1-Global cryomodule is presented. INTRODUCTION The S1-Global cryomodule was proposed and approved as an international collaborative effort at the SCRF meeting of the ILC Global Design Effort in April 2008. The goals of the S1 Global program are to attempt to achieve an average accelerating gradient of 31.5MV/m across 8 cavities. To accomplish this, eight cavities and couplers are contributed from FNAL, DESY and KEK, and installed in two ‘half cryomodules’ each 6 m long: Module-C, a new cryomodule designed and constructed by INFN; and Module-A, a modified STF cryomodule by KEK. The S1-G cryomodule design work was completed in January 2009, and the assembly started in January 2010. The collaborative framework of S1-G is demonstrated in the contributions of the participating laboratories: INFN: Design and construction Module-C and production of the blade tuners for the FNAL cavities. FNAL: Two TESLA type cavities [2], power couplers and integration of the INFN blade tuners in the cavity packages. DESY: Two TESLA type cavities, including Saclaytype tuners, and power couplers. SLAC: Power distribution for Module-C, and aging of FNAL couplers. KEK: Four TESLA-like cavities, with two types of tuner design, Module-A for KEK cavities [3], power distribution for Module-A, and infrastructure for tests. DESIGN OF S1-GLOBAL CRYOMODULE The S1-Global assembly is shown in Fig. 1. Two cavities from FNAL and two form DESY are installed in the Module-C, and four cavities of two types by KEK are installed in Module-A. The total length of the S1-Global assembly is 14.9 m. The parameters of the two cryomodules are listed in Table 1. The cross section of Module-C has the same design as the TTF-type III cryomodule [4]. The cold mass is supported to the vacuum vessel by two composite cylindrical posts spaced 3200 mm apart. All four input couplers are separated by a distance of 1384.15 mm at room temperature. The designs of FNAL and DESY cavity packages differ because of the tuner types, the Blade tuner and the Saclay-type tuner. The difference in length is made up in the bellows between packages. Fig.1: S1-G cryomodule and cavity package of each laboratory. (a): FNAL cavity with Blade tuner, (b): DESY cavity with Saclay-type tuner, (c): KEK-a cavity with slide jack tuner and (d) KEK-b cavity. WEPE008 Proceedings of IPAC’10, Kyoto, Japan 3356 03 Linear Colliders, Lepton Accelerators and New Acceleration Techniques A03 Linear Colliders Table 1: S1-Global Cryomodule Parameters