Conductor for LHC Upgrades Hi- Lumi -LARP Annual Meeting Frascati , November 2012 A. Ballarino

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Conductor for LHC Upgrades Hi-Lumi-LARP Annual Meeting Frascati, November 2012 A. Ballarino allarino, B. Bordini, L. Bottura, L. Oberli and L. CERN, European Center for Nuclear Research, Geneva Switzerland

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Conductor for LHC Upgrades Hi- Lumi -LARP Annual Meeting Frascati , November 2012 A. Ballarino. Ballarino, B. Bordini , L. Bottura, L. Oberli and L. Rossi CERN, European Center for Nuclear Research, Geneva Switzerland. LHC Performance . LHC: week 43 E= 4 TeV /beam - PowerPoint PPT Presentation

Transcript of Conductor for LHC Upgrades Hi- Lumi -LARP Annual Meeting Frascati , November 2012 A. Ballarino

Slide 1

Conductor for LHC UpgradesHi-Lumi-LARP Annual MeetingFrascati, November 2012A. BallarinoBallarino, B. Bordini, L. Bottura, L. Oberli and L. Rossi

CERN, European Center for Nuclear Research, Geneva SwitzerlandA. BallarinoLHC Performance

LHC: week 43E= 4 TeV/beamPeak luminosity = 7.51033 cm-2 s-1Int. luminosity in 2012 = 18.4 fb-1Courtesy of S. Myers, June 2012

LUMINOSITY BEAM INTENSITYLHC Performance A. BallarinoH-Lumi Meeting, Frascati, Nov. 2012A. BallarinoFIELD ERRORS PARTICLE LOSSESFIELD QUALITY STABILITY AND CONTROL OF THE BEAM Conductor for HE accelerator magnets To maintain luminosity, particle losses must be limited. Multiple field errors lead to particle losses which reduce the beam lifetime The field quality specification must meet the criteria for stability and control of the beam DA calculations: Courtesy of B. Holzner|b3| < 27 unitsA single IR with 2 modified bending dipoles with a b3 (sextupole) error in the range of few 10-3 would induce a visible degradation

Compensations and corrections are feasible, but result in reduced flexibility (e.g. new ATS optics where local can be increased by a factor 5)

A. BallarinoConductor for HE accelerator magnetsEffect of sextupole components on dynamic aperture of the beam11 T Dipole Project Number of sigma. Apertura dinamica (beam life time) piu grande5A. BallarinoThe effect of large filaments is twofold:Larger absolute field errorLarger field swing (penetration)

Injection current (760 A)Effect of Nb3Sn magnetization on the sextupole field of a 11 T DS-MB operated at 1.9 KConductor for Hi-Luminosity LHC11 T Dipole Project Deff < 30 mA. BallarinoConductor Specification JC (kA/mm2)Dfil (m)RRR (-)PerformancePeak fieldCostStability ProtectionMagnetization Field QualityStability2.521.533.51420015010050102050100targetDream wiretarget performance:Jc > 3 kA/mm2Dfil < 20 m RRR > 150*

* Virgin strandHi-Luminosity wiretarget performance:Jc > 2.5 kA/mm2Dfil < 30 m RRR > 150*

Specification of conductorA. Ballarino

Binj=0.535 TIinj=736 A8A. BallarinoMagnetization instability (1/3)Measurement of several virgin strands in the VSM CERN test station

- different temperatures (1.9 K to 14.5 K, He gas environment) - different fields (up to 10.5 T)

RRP54/61108/127132/169198/217PIT114192Magnetization instability (2/3)A. BallarinoJc, Deff, RRR

Measurements by D. RichterA. Ballarino

Magnetization instability (3/3)

Deff of RRP wires larger (12 %-23 %) than diameter of sub-elem. before reactionDeff of PIT wires diameter of sub-elem. before reactionMeasurements by D. RichterPIT, 11 T Dipole Project RRP, 11 T Dipole Project A. BallarinoSelf-field instability (1/4)

Bordinis plotSelf-field instability (2/4)A. BallarinoIc-station equipped with a 100 um core optical fibreFibre connected to Q-Switched UV-Laser 355 nm (or 532 nm green)Other end of the fibre is on top of the strandStrand is mounted on a VAMAS barrelPulse width ~1 ns!Single shot

26 uJ/pulse absorbed energyAttenuator (2%-100%) 0.5 uJ 26 uJ

[2] E. Takala et. al., An Experimental Setup to Measure the Minimum Trigger Energy for Magneto-Thermal Instability in Nb3Sn Strands, IEEE Trans. Appl. Supercond. vol. 22 no. 3, pp. 6000704, 2012.PhD Thesis of E. TakalaSelf-field instability (3/4)Full characterization with the LQT System of RRP 108/127, 0.7 mm (11 T dipole strand)

Jc(4.3 K,12 T) = 2670 A/mm2

4.3 KRRR = 129 A. Ballarino

1.9 K11.2 TE. TakalaA. Ballarino0.7 mm RRP: RRR 21 vs 129 at 4.3 KSelf-field instability (4/4)

E. TakalaReview paper of A. Ghosh, ASC 2012, 4MF-01Mechanical propertiesA. Ballarino

Ic vs transversal stress StrandMeasurements at UNIGE

PIT 288, = 1.25 mm

G. Mondonico, UNIGEHFM Nb3Sn cables

FRESCA 2 cableRectangular un-cored cablePIT 192 , 40 strands, = 1 mm (cabled)RRP 132/169, 40 strands, = 1 mmWidth = 20.9 mmThickness = 1.82 mmTransposition pitch = 120 mmCompaction factor = 87.6 %Measured Ic degradation (extracted strands) 5 %

A. Ballarino

PIT 192Up to now, only Fresca cables from PIT strands were made at CERNHFM Nb3Sn cables

FRESCA 2 cableRRR of extracted strandsPerformance of PIT round strands are according to specificationA. BallarinoRound shaped filaments enable a concentric movement of the Nb3Sn reaction front high Jc and high RRR B3= systematic error, flux jump = random errors18A. Ballarino11 T cableHFM Nb3Sn cablesKeystoned cored cableCore = AISI 316 L, 12 mm width, 25 m thicknessRRP 108/127, 40 strands, = 0.7 mm (cabled)PIT 102 , 40 strands, = 0.7 mm (to be cabled in the next weeks)Width = 14.7 mmTransposition pitch = 100 mmKeystone angle = 0.79oCompaction factor = 87.3 %Measured Ic degradation (extracted strands) cored cables 1 %

Cored cable(UL = 230 m)Mechanical propertiesA. BallarinoIc vs transversal pressure Cable 11 T cable: 40 strands, =0.7 mm, RRP 108/127,

Ic(4.2 K, 11.T)=17.6 kAMeasurements @ Twente UniversityA. BallarinoMechanical properties

Ic vs transversal pressure CableCERN sample holderIrradiation (1/4)A. BallarinoHigh energy sources [%]photons88electrons/positrons7neutrons4pions0.45protons0.15High Lumi LHC target: integrated luminosity (3000 fb-1). Triplet quadrupole cables and insulators will undergo the following radiation peak values: ~ 100 MGy (dose) ~ 1016 pions/cm2 ~ 2 x 1017 neutrons/cm2 Neutrons87.0 %Protons 3.2%Pions (+/-) 9.8% F. CeruttiIrradiation (2/4)A. Ballarino24 GeV proton irradiation at CERN, IRRAD1 (PS beam). Up to 31013 p/cm2 per hour. Maximum fluence of 1017 p/cm2 has been accumulated during 2011 and 2012

1.4 GeV proton irradiation at CERN on ISOLDE target (booster beam). Catherall. Relatively high fluences >1017 p/cm2 can be achieved within one week

65 MeV proton irradiation at Cyclotron of Universit catholique de Louvain (UCL). About 81015 p/cm2 per hour. Maximum fluence was 1017 p/cm2

30 MeV proton irradiation of Nb3Sn and Ic transport current measurement samples planned at Kurchatov Institute, Moscow. Maximum targeted fluence is 1018 p/cm2

Fast neutron irradiation at the TRIGA reactor in Vienna

Irradiation (3/4)A. Ballarino

Fast neutron irradiation at the TRIGA reactor in Vienna

RRP +Ta, =0.8 mmRRP + Ti, =0.8 mmPIT +Ta, =1 mmIT +Ta, =1.25 mm

A. BallarinoIrradiation (4/4)

Neutron irradiation: Variation of Jc with increasing neutron fluenceR. Flukiger et al.ASC 2012,

Conclusions A. BallarinoUpgrading the LHC will not be easy

Todays wires and cables are perfectly adequate for the model and prototyping phase

Nb3Sn needs a final push to demonstrate the quality, uniformity and yield required by the two main magnet phases of HL-LHC (11 T, quads)A. BallarinoThanks for your attention !