LARP Magnet R

1
LARP Magnet RD at FermilabAlexander Zlobin,
Fermilab
US LHC Accelerator Research Program

brookhaven - fermilab - berkeley

• Outline
• New generation IRQ

2
LARP

• Fermilab actively participated in launching the
  U.S. LHC Accelerator Research Program (LARP) and
  will continue play key role in the Program.
• The goal of LARP magnet RD is to develop 2nd
  generation IR magnets for LHC to replace the 1st
  generation magnets.
• Contributions of Fermilab to LARP Magnet RD
  include
• conceptual designs studies of various magnets for
  2nd generation LHC IRs
• participation in material and component
  development
• leading the IRQ short and long model magnet RD
• design, fabrication and tests of full-scale
  prototypes of the LHC IR magnets
• Close BNL-Fermilab-LBNL collaboration and strong
  connection between the LARP magnet RD program
  and the base High Field Magnet RD programs is
  critical, in order to reduce risks and increase
  the probability of success.
• Base magnet RD programs for Nb3Sn HFM should be
  able to demonstrate the possibilities and
  limitations for this technology during next
  couple of years.

3
1st Generation LHC IRs

• Baseline LHC inner triplets consist of
  single-bore, high-gradient quads based on NbTi
  superconductor.
• Quadrupole parameters
• 70 mm coil aperture
• 205 T/m nominal gradient with 20 margin
• 1.9 K operating temperature

4
2nd generation Inner Triplet Design Options

• Two fundamental inner triplet design approaches
  to 2nd generation LHC IRs
• a) single-bore inner triplet design
• Quadrupoles with largest possible aperture are
  required, to provide largest beam separation and
  accommodate the large b-max.
• b) dipole-first designs with double-bore
  quadrupoles
• For these IR designs there are two contradictory
  requirements for IR quads
• Large b-max requires large aperture
• Twin-bore configuration limits aperture

5
Double-bore Inner Triplet Designs
Parallel apertures Non-parallel apertures
Examples of 2nd generation LHC IR optics based on
double-bore inner triplet with 100 mm quads.
6
RD Questions

• RD questions
• What is the optimal maximum field for new Nb3Sn
  IRQ?
• What is the optimum operation margin in the
  extreme radiation environment at very high
  luminosity?
• What is the IRQ optimum aperture for single-bore
  and double-bore quads?
• What is the optimal design for large-aperture
  Nb3Sn quads?
• Are non-parallel axis double-bore quadrupoles
  feasible?
• How to maintain good field quality in magnets
  over the full operating range?
• How to remove the large heat deposition (few kW)
  from the magnet cold mass?
• What are appropriate materials for operational
  conditions?
• These questions have to be addressed during
  conceptual design studies and model magnet RD.

7
Common Quadrupole and Dipole Features

• Many of RD issues are common to new IR dipoles
  and quadrupoles
• Conductor issues
• new Nb3Sn high-Jc strands
• Strand and cable stability, magnetization,
  degradation
• Maximum field and field quality
• Mechanics and high-stress management
• Coil cooling and heat transfer to cryogenic
  system
• Quench protection
• Materials and components (high radiation
  insulation)
• Technology react and wind approach
• The tight connection and cross-talk of both
  magnet RD directions and general technology
  development is natural and will lead to the high
  efficiency of the whole program.

8
Phases and Milestones

• FY04-FY05 conceptual design studies
• FY06 - start IRQ model RD with simplified 1-m
  long models (2-layer design) in order to develop
  basic tooling and infrastructure and start basic
  technology development.
• FY07-FY10 - a series of short models will address
  the issues of magnet quench performance, field
  quality, mechanics, quench protection,
  reproducibility, long term performance, etc.
• FY08 - start studying length dependent effects
  with 4-m long coils, as soon as we achieve
  acceptable quench performance.
• FY10-FY12 - construction of one or more
  prototypes containing all of the features
  required for use in the LHC.

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FY04-FY05 goals and collaboration

• Establish baseline IRQ design for the first phase
  of short model RD, including
• magnet cross-section
• strand and cable parameters
• mechanical structure of magnet cold mass
• Continue conceptual design studies of D1 design,
  including
• magnetic and mechanical design
• thermal design and analysis
• quench protection analysis
• Status of work at Fermilab in these areas will be
  presented by Vadim.

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Other areas for collaboration

• Nb3Sn strand and cable RD
• Strand testing
• stability and magnetization studies
• cable design, fabrication and testing
• Ic degradation and interstrand resistance studies
• Material and component development
• ceramic or S2-glass insulation with ceramic
  pre-preg
• end part design and fabrication
• Test of radiation resistant impregnation
  materials based on liquid poliimid
• Quench heater design, fabrication and test
• Passive correction design, fabrication and test
• WR technology
• coil winding, curing, HT and impregnation
  techniques
• Splicing technology
• Tooling design
• Magnet assembly technique