Thursday Summary of Working Group I

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Thursday Summary of Working Group I
LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 1
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Thursday Summary of Working Group I
LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 2
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Thursday Summary of Working Group I
-create a repository for different layout
configurations and optics solutions ? common
data base for future studies ? common reference
for future discussions ? will be discussed on
Friday -interesting modular proposal for
maximizing F by additional dipole inside
experiment ? all insertion scenarios benefit ?
should be pursued independently of final IR
design -NiTi is not a viable solution for IR
upgrade ? is this true for all IR layout and
optics proposals (e.g. low gradient triplet
solution)? ? will be discussed on Friday
LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 3
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Thursday Summary of Working Group I
-two options for dealing with the increased heat
load inside the triplet magnets 1) construct
more robust triplet magnets that can tolerate
the increased peak heat load 2) reduce the
peak heat load with an upgrade of the TAS
absorber
LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 4
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Thursday Summary of Working Group I

• 1) construct more robust triplet magnets that
  can tolerate
• the increased peak heat load
• ? structured cable design with Ni3Sn and Inconel
  718 jacket
• Iron less quadrupoles for Q1 with 340 T/m 40mm
  aperture
• and expected heat tolerances of gt 50 W/m
• Strong mechanical support and low inductance for
  large
• quench induced voltages
• Confidence that Ni3Sn is matured technology by
  2010?
• Disuccion Inconel jacket could also be used
  with NiTi?

LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 5
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Design Q1 using structured cable
6-on-1 cabling of Nb3Sn strand around thin-wall
inconel X750 spring tube Draw within a thicker
inconel 718 jacket Interior is not impregnated
only region between cables in winding Volumetric
cooling to handle volumetric heating from
particle losses
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Thursday Summary of Working Group I

• 2) reduce the peak heat load with an upgrade of
  the TAS
• absorber
• ? levitated dipole coil design with opening at
  room temperature
• B 8.7 T at 4.5 K Ni3Sn only at inner coil NiTi
  otherwise
• interesting magnet design for a magnetic TAS
  option

LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 7
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D1 levitated-pole dipole
8.7 T 4.5 K
Cold iron pole piece, warm iron flux
return. Cancel Lorentz forces on coils, pole
steel.
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Thursday Summary of Working Group I

• -compensate Lorentz force on the coils by using
  two race
• track coils ? 15 T field for Ni3Sn and 8T for
  NiTi
• -open mid plane and possibility of installing
  dedicated
• absorber material
• Interesting option for magnetic TAS design
• Who is following this research up? US-LARP has
  decided
• to suspend dipole RD and to concentrate on
  quadrupoles!

LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 9
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OMD Design Challenges

• Counteracting large vertical forces between the
  coils without any structure appears to be a
  challenge.
• Good field quality maybe a challenging task due
  to large midplane gap.
• Large Bpeak/Bcenter ratio in magnets with large
  midplane gap may reduce operating field.
• The optimum design may look totally different.

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A True Open Midplane Design
In earlier OMD designs, absorbers were placed
between the the coils. Secondary showers from the
absorber deposited a large amount of radiation
and heat load on the coils. This problem is fixed
in the new design.
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Thursday Summary of Working Group I
-geometric reduction factor can be reduced with
the help of CRAB cavities (transverse kick ?
alternative to JPK dipole) -LHC parameters
requires between 4MV (small crossing angle) and
100 MV voltage for f 400MHz ?? 800 MHz -small
emittance blowup requires turn-by-turn phase
control of better than 0.01 degrees -CRAB
cavities require sufficient large beam
separation (? installation after D2 plus dog leg
separation?)
LHC LUMI 2005 2.9.2005 Arcidosso
Oliver Brüning 12
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Super-KEKB crab cavity scheme
2 crab cavities / beam / IP
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voltage required for Super-LHC