Electrical Quality Assurance of the Superconducting Circuits during LHC Machine Assembly

Based on the LHC powering reference database, all-together 1750 superconducting circuits were connected in the various cryogenic transfer lines of the LHC machine. Testing the continuity, magnet polarity, and the quality of the electrical insulation were the main tasks of the Electrical Quality Assurance (ELQA) activities during the LHC machine assembly. With the assembly of the LHC now complete, the paper reviews the work flow, resources, and the qualification results including the different types of electrical non-conformities

FIRST CRYOMODULE TEST AT AMTF HALL FOR THE EUROPEAN X-RAY FREE ELECTRON LASER (XFEL)

Abstract The Accelerator Module Test Facility (AMTF) at DESY in Hamburg is dedicated to the tests of RF cavities and accelerating cryomodules for the European X-ray Free Electron Laser (XFEL). The AMTF hall is equipped with two vertical cryostats, which are used for RF cavities testing and three test benches that will be used for tests of the accelerating cryomodules. Recently, the first cryomodule teststand (XATB3) was commissioned and the first XFEL cryomodule (XM-2) was tested by team of physicists, engineers and technicians from The Henry

IFJ PAN's contribution to the HL-LHC: construction of the superconducting links

New superconducting transfer lines known as Superconducting Links (SC Links) are being developed at CERN for the remote powering of upgraded superconducting insertion magnets in the framework of the High Luminosity Large Hadron Collider (HL-LHC) project. The purpose of the SC Links is to transfer current from power converters located in radiation-free areas to magnets located in the vicinity of the LHC interaction points via shorter REBCO High Temperature Superconductor (HTS) current leads. HTS current leads, connecting the superconducting link to the conventional cables of the power converters, allow a very high current densities to be carried and significantly reducing the cooling power required for conventional cables. The expected length of the superconducting lines can reach 130 m, depending on the location, spanning a vertical distance of about 80 m. Each of the link containing an assembly of MgB$_2$ cables supplying different systems, which will transfer a total current exceeding 150 kA. In order to validate the selected technical solutions and materials as well as to confirm the design reliability and robustness of the SC Links, the construction of a fully functional 60 m long demonstrator (DEMO1) of the 18 kA circuit of the SC Link is ongoing. Since 2018, the engineering team from IFJ PAN has been contributing to the Cold Powering activity (Work Package 6a of the HL-LHC project). This contribution includes among others, preparing of assembly procedures for the system, producing components for the demonstrator, assembling the demonstrator and participating in tests

IFJ PAN’s contribution to the HL-LHC: DQW crab cavity preparation and testing at CERN

The Double Quarter Wave (DQW) Crab Cavity was designed to rotate the colliding bunches and in consequence to increase the luminosity of the LHC machine. Prior to launching series production detailed RF validation tests, both without and with beam, were performed at CERN. For the cavity preparation and RF performance validation before installation in the cryomodule, a comprehensive programme of RF surface preparation and cavity performance evaluation in liquid helium temperatures were carried out. Due to the unusual geometry of the DQW cavity there were a number of challenges both in preparation and RF testing that had to be addressed. The results and conclusions of the preparation process and cavity performance in the vertical test cryostat are presented in this paper in the form of a short technical report

IFJ PAN’s contribution to the HL-LHC: crab cavities and RF

The High Luminosity LHC (HL-LHC) Project is an upgrade program of the Large Hadron Collider (LHC) at CERN, focused on increasing the luminosity, thus significantly enhancing the potential to discover new physics from rare events. Among many activities ongoing in this framework, the implementation of novel superconducting radio frequency (SRF) cavities - especially Crab Cavities - is foreseen for compensation of the bunch crossing angle, which is a reducing factor for LHC luminosity. Two different crab cavity designs have been developed: the Double Quarter Wave (DQW) and the Radio Frequency Dipole (RFD). A prototype cryomodule, hosting two DQW cavities, has been fabricated and assembled3 for validation tests, which are currently ongoing in the Super Proton Synchrotron (SPS) at CERN. Since 2016 the engineering team from IFJ PAN has been contributing to the Crab Cavities & RF project (Work Package 4 of the HL-LHC Project). This contribution has included the following activities: mechanical, electrical and vacuum preparation of DQW crab cavities for cold tests in the vertical cryostat, as well as the assembly process of the fully-dressed DQW cavities. After successful RF cavities qualification, the assembly of the DQW cryomodule and its preparation for the tests was also performed with the participation of the IFJ PAN team