Design of a 120 mm Bore 15 T Quadrupole for the LHC Upgrade Phase II

Section: Mechanical Design Of Mqxfmentioning

confidence: 99%

Mechanical Design Studies of the MQXF Long Model Quadrupole for the HiLumi LHC

Pan¹,

Anderssen²,

Ambrosio³

et al. 2017

“…As the first LARP design incorporating all provisions for accelerator field quality [1], [2], the main goal of the HQ magnets is to demonstrate the performance requirements for the 150 mm aperture Nb 3 Sn low-β quadrupole magnet to be used at the interaction region of the High-Luminosity LHC [3]- [5].…”

Section: Introductionmentioning

confidence: 99%

Analysis of Field Errors for LARP Nb$_3$ Sn HQ03 Quadrupole Magnet

Wang

Ambrosio

Chlachidze

et al. 2017

Abstract-The U.S. LHC Accelerator Research Program, in close collaboration with CERN, has developed three generations of high-gradient quadrupole (HQ) Nb3Sn model magnets, to support the development of the 150 mm aperture Nb3Sn quadrupole magnets for the High-Luminosity LHC. The latest generation, HQ03, featured coils with better uniformity of coil dimensions and properties than the earlier generations. The HQ03 magnet was tested at FNAL, including the field quality study. The profiles of low-order harmonics along the magnet aperture observed at 15 kA, 1.9 K can be traced back to the assembled coil pack before the magnet assembly. Based on the measured harmonics in the magnet center region, the coil block positioning tolerance was analyzed and compared with earlier HQ01 and HQ02 magnets to correlate with coil and magnet fabrication. To study the capability of correcting the low-order non-allowed field errors, magnetic shims were installed in HQ03. The expected shim contribution agreed well with the calculation. For the persistent-current effect, the measured a4 can be related to 4% higher in the strand magnetization of one coil with respect to the other three coils. Finally, we compare the field errors due to the inter-strand coupling currents between HQ03 and HQ02.Index Terms-LARP, Nb3Sn quadrupole magnets, field quality.

“…Its main goal is to provide a technology basis for the 150 mm aperture low-β quadrupoles (MQXF) that will be installed in the interaction regions of the High Luminosity LHC [2]. The first phase of the HQ program included production of eight coils, and five assembly cycles (HQ01a-HQ01e) [3][4][5][6]. These models, while demonstrating operation well above the HQ target gradient of 170 T/m, were affected by stress degradation, electrical insulation failures, and large dynamic field errors [7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Test Results of the LARP Nb3Sn Quadrupole HQ03a

DiMarco

Ambrosio

Anerella

et al. 2016

Abstract-The US LHC Accelerator Research Program (LARP) has been developing Nb3Sn quadrupoles of increasing performance for the high luminosity upgrade of the Large Hadron Collider. The 120 mm aperture High-field Quadrupole (HQ) models are the last step in the R&D phase supporting the development of the new IR Quadrupoles (MQXF). Three series of HQ coils were fabricated and assembled in a shell-based support structure, progressively optimizing the design and fabrication process. The final set of coils consistently applied the optimized design solutions, and was assembled in the HQ03a model. This paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.