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Initial questions I:. Thursday Summary of Working Group I. LHC LUMI 2005; 2.9.2005; Arcidosso. Oliver Brüning 1. Initial questions II:. Thursday Summary of Working Group I. LHC LUMI 2005; 2.9.2005; Arcidosso. Oliver Brüning 2. main points from morning session for working group I:.
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Initial questions I: Thursday Summary of Working Group I LHC LUMI 2005; 2.9.2005; Arcidosso Oliver Brüning 1
Initial questions II: Thursday Summary of Working Group I LHC LUMI 2005; 2.9.2005; Arcidosso Oliver Brüning 2
main points from morning session for working group I: 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
main points from Peter McIntyre’s presentation I: 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
main points from Peter McIntyre’s presentation II: 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 > 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
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
main points from Peter McIntyre’s presentation III: 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
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.
main points from Rama Calaga’s presentation: 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 R&D and to concentrate on quadrupoles! LHC LUMI 2005; 2.9.2005; Arcidosso Oliver Brüning 9
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/Bcenterratio in magnets with large midplane gap may reduce operating field. The optimum design may look totally different.
A True Open Midplane Design In earlier “OMD designs”, absorbers were placed between the the coils. Secondary showers from the absorberdeposited a large amount of radiation and heat load on the coils. This problem is fixed in the new design.
main points from Frank Zimmermann’s presentation I: 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
Super-KEKB crab cavity scheme 2 crab cavities / beam / IP