skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Conductor Specification and Validation for High-Luminosity LHC Quadrupole Magnets

Abstract

© 2017 IEEE. The high-luminosity upgrade of the large hadron collider (HL-LHC) at CERN will replace the main ring inner triplet quadrupoles, identified by the acronym MQXF, adjacent to the main ring intersection regions. For the past decade, the U.S. LHC Accelerator R&D Program, LARP, has been evaluating conductors for the MQXFA prototypes, which are the outer magnets of the triplet. Recently, the requirements for MQXF magnets and cables have been published in [P. Ferracin et al., IEEE Trans. Appl. Supercond., vol. 26, no. 4, Jun. 2016, Art. no. 4000207], along with the final specification for Ti-alloyed Nb3Sn conductor determined jointly by CERN and LARP. This paper describes the rationale beneath the 0.85-mm-diameter strand's chief parameters, which are 108 or more subelements, a copper fraction not less than 52.4%, strand critical current at 4.22 K not less than 631 A at 12 T and 331 A at 15 T, and residual resistance ratio of not less than 150. This paper also compares the performance for ~100 km production lots of the five most recent LARP conductors to the first 163 km of strand made according to theHL-LHCspecification.Two factors emerge as significant for optimizing performance and minimizing risk: a modest increasemore » of the subelement diameter from 50 to 55 μm, and a Nb:Sn molar ratio of 3.6 instead of 3.4. The statistics acquired so far give confidence that the present conductor can balance competing demands in production for the HL-LHC project.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP)
Contributing Org.:
LARP
OSTI Identifier:
1340492
Alternate Identifier(s):
OSTI ID: 1340481; OSTI ID: 1580090
Report Number(s):
FERMILAB-CONF-16-344-TD
Journal ID: ISSN 1051-8223; 1510202; TRN: US1700515
Grant/Contract Number:  
AC02-07CH11359; AC02-05CH11231
Resource Type:
Accepted Manuscript
Journal Name:
IEEE Transactions on Applied Superconductivity
Additional Journal Information:
Journal Volume: 27; Journal Issue: 4; Journal ID: ISSN 1051-8223
Publisher:
Institute of Electrical and Electronics Engineers (IEEE)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; RRR; critical current; magnet conductors; Nb3Sn; niobium tin superconductors; quadrupole magnets; residual resistance ratio

Citation Formats

Cooley, L. D., Ghosh, A. K., Dietderich, D. R., and Pong, I. Conductor Specification and Validation for High-Luminosity LHC Quadrupole Magnets. United States: N. p., 2017. Web. https://doi.org/10.1109/TASC.2017.2648738.
Cooley, L. D., Ghosh, A. K., Dietderich, D. R., & Pong, I. Conductor Specification and Validation for High-Luminosity LHC Quadrupole Magnets. United States. https://doi.org/10.1109/TASC.2017.2648738
Cooley, L. D., Ghosh, A. K., Dietderich, D. R., and Pong, I. Thu . "Conductor Specification and Validation for High-Luminosity LHC Quadrupole Magnets". United States. https://doi.org/10.1109/TASC.2017.2648738. https://www.osti.gov/servlets/purl/1340492.
@article{osti_1340492,
title = {Conductor Specification and Validation for High-Luminosity LHC Quadrupole Magnets},
author = {Cooley, L. D. and Ghosh, A. K. and Dietderich, D. R. and Pong, I.},
abstractNote = {© 2017 IEEE. The high-luminosity upgrade of the large hadron collider (HL-LHC) at CERN will replace the main ring inner triplet quadrupoles, identified by the acronym MQXF, adjacent to the main ring intersection regions. For the past decade, the U.S. LHC Accelerator R&D Program, LARP, has been evaluating conductors for the MQXFA prototypes, which are the outer magnets of the triplet. Recently, the requirements for MQXF magnets and cables have been published in [P. Ferracin et al., IEEE Trans. Appl. Supercond., vol. 26, no. 4, Jun. 2016, Art. no. 4000207], along with the final specification for Ti-alloyed Nb3Sn conductor determined jointly by CERN and LARP. This paper describes the rationale beneath the 0.85-mm-diameter strand's chief parameters, which are 108 or more subelements, a copper fraction not less than 52.4%, strand critical current at 4.22 K not less than 631 A at 12 T and 331 A at 15 T, and residual resistance ratio of not less than 150. This paper also compares the performance for ~100 km production lots of the five most recent LARP conductors to the first 163 km of strand made according to theHL-LHCspecification.Two factors emerge as significant for optimizing performance and minimizing risk: a modest increase of the subelement diameter from 50 to 55 μm, and a Nb:Sn molar ratio of 3.6 instead of 3.4. The statistics acquired so far give confidence that the present conductor can balance competing demands in production for the HL-LHC project.},
doi = {10.1109/TASC.2017.2648738},
journal = {IEEE Transactions on Applied Superconductivity},
number = 4,
volume = 27,
place = {United States},
year = {2017},
month = {6}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 2 works
Citation information provided by
Web of Science

Save / Share:

Works referencing / citing this record:

Precipitous change of the irreversible strain limit with heat-treatment temperature in Nb3Sn wires made by the restacked-rod process
journal, August 2018


Implications of the strain irreversibility cliff on the fabrication of particle-accelerator magnets made of restacked-rod-process Nb3Sn wires
journal, April 2019


An intermetallic powder-in-tube approach to increased flux-pinning in Nb 3 Sn by internal oxidation of Zr
journal, November 2017

  • Motowidlo, L. R.; Lee, P. J.; Tarantini, C.
  • Superconductor Science and Technology, Vol. 31, Issue 1
  • DOI: 10.1088/1361-6668/aa980f

More time for Nb 3 Sn magnet conductors
journal, September 2018


Ternary Nb 3 Sn superconductors with artificial pinning centers and high upper critical fields
journal, January 2019


Dipole Magnets Above 20 Tesla: Research Needs for a Path via High-Temperature Superconducting REBCO Conductors
journal, November 2019