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Collector and the SPL Super-Beam Project . Marcos Dracos IPHC-IN2P3/CNRS Strasbourg. Staging neutrino facilities towards the NF Cover "high" q 13 range Cost effective facility Low intensity SPL already approved,
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Collector and the SPLSuper-Beam Project Marcos Dracos IPHC-IN2P3/CNRS Strasbourg M. Dracos, EUROnu-WP2
Staging neutrino facilities towards the NF • Cover "high" q13 range • Cost effective facility • Low intensity SPL already approved, • Detector could already be approved to cover other physics subjects (proton life-time, cosmological neutrinos…) Why this SB? M. Dracos, EUROnu-WP2
Present and future injectors Proton flux / Beam power Linac4 Linac2 50 MeV Stage 1 (2013) 160 MeV (LP)SPL PSB Stage 2 (2017) 1.4 GeV 4 GeV (LP)SPL: (Low Power) Superconducting Proton Linac (4-5 GeV) PS2: High Energy PS (~ 5 to 50 GeV – 0.3 Hz) SPS+: Superconducting SPS (50 to1000 GeV) SLHC: “Superluminosity” LHC (up to 1035 cm-2s-1) DLHC: “Double energy” LHC (1 to ~14 TeV) PS 26 GeV PS2 50 GeV Output energy SPS SPS+ 450 GeV 1 TeV LHC / SLHC DLHC 7 TeV Stage 3 (>2017): HP-SPL ~ 14 TeV June 23-27, 2008 3 R.G. M. Dracos, EUROnu-WP2
180 MeV 5 GeV 50 MeV 643 MeV 3 MeV 102 MeV H- source RFQ DTL chopper CCDTL PIMS β=0.65 β=1.0 352.2 MHz 704.4 MHz Stage 3: HP-SPL Linac4 (160 MeV) SC-linac (5 GeV) Length: 540 m HP-SPL beam characteristics June 23-27, 2008 4 R.G. M. Dracos, EUROnu-WP2
SPL Super-Beam Project Accumulator ring + bunch compressor H- linac 2.2, 3.5 or 5 GeV, 4 MW p proton driver to be studied in EURO WP2 Magnetic horn capture (collector) p Target hadrons n, m decay tunnel ~300 MeV nm beam to far detector to be studied by LAGUNA M. Dracos, EUROnu-WP2
SPL (CDR2) main characteristics butch compressor to go down to 3.2 s (important parameter for hadron collector pulsing system) (possible energy upgrade to 5 GeV could be the subject of a 3rd CDR) M. Dracos, EUROnu-WP2
Proton Target very challenging task • 300-1000 J cm-3/pulse • Severe problems from : sudden heating, stress, activation • Safety issues ! • Baseline for Super-Beam is solid target, mercury is optional (baseline for NF) • Extremely difficult problem : need to pursue two approaches : • Liquid metal target (Merit experiment) • Solid target (extensive R/D program at STFC and BNL) • Envisage alternative solutions M. Dracos, EUROnu-WP2
CC target He OUT He IN fluidised jet of particles some ideas Proposed rotating tantalum target ring (realistic?) Horn Proton Target Helium cooling of target Liquid Mercury (MERIT) Work at BNL and RAL Experience on T2K target (750 kW) very useful cooling is a main issue… M. Dracos, EUROnu-WP2
Proposed collection system horn proton beam 3.7 cm 8.5° 300 kA 4 cm target 16.6 cm 40 cm 80 cm taking into account the proton energy and collection efficiency, the target must be inside the horn M. Dracos, EUROnu-WP2
Hadron production Particles coming out of the target 2.2 GeV protons pT distribution not the same for all targets the choice of the target could influence the hadron collection system (horn shape) pT From now on Hg will be considered M. Dracos, EUROnu-WP2
Hadron production uncertainties 2.2 GeV protons disagreement between models (Monte Carlo production, interaction and transport codes) p+ momentum more development is needed (simulation, measurements) M. Dracos, EUROnu-WP2
Proton Energy and Pion Spectra • pions per proton on target. • Kinetic energy spectrum • 2.2 GeV: • <Ek>=300MeV • 3.5 GeV: • <Ek>=378MeV interesting region for SPL SB Ekine (GeV) 1GeV 2GeV cos q hadrons boosted forward 1 0 -1 M. Dracos, EUROnu-WP2
Proposed design for SPL for pions coming out of the target 500 < pp < 700 MeV/c p+ angle p+ momentum horn region (0.26-1.22 rad) for a Hg target, 30 cm length, 15 mm (Nparticlesx1016/sec, FLUKA) relatively better collection when pproton the target must be inside the horn M. Dracos, EUROnu-WP2
2.2 GeV proton beam : <pp> = 405 MeV/c <qp> = 60° 3.5 GeV proton beam : <pp> = 492 MeV/c <qp> = 55° Horn geometry I = 300 kAmp I = 300 kAmp r(m) r(m) B~1/r B~1/r B must be 0 B must be 0 4 cm 4 cm target target 30 cm z(m) 30 cm z(m) M. Dracos, EUROnu-WP2
600 kA reflector horn proton beam 3.7 cm 8.5° 300 kA 4 cm Hg target 16.6 cm 12.9° 20.3 cm 4 cm 40 cm 80 cm 70 cm Proposed design for SPL horn+reflector very high current and frequency inducing severe problems M. Dracos, EUROnu-WP2
48.2 kW 67kW 14.9kW 78.7kW Energy deposition in the conductors • MARS +8kW from Joule effect 4MW, 2.2 GeV proton beam (1MeV = 1.82 kW) M. Dracos, EUROnu-WP2
Main Technical Challenges • Horn : as thin as possible (3 mm) to minimize energy deposition, • Longevity in a high power beam (currently estimated to be 6 weeks!), • 50 Hz (vs a few Hz up to now), • Large electromagnetic wave, thermo-mechanical stress, vibrations, fatigue, radiation damage, • Currents: 300 kA (horn) and 600 kA (reflector) • design of a high current pulsed power supply (300 kA/100 μs/50 Hz), • cooling system in order to maintain the integrity of the horn despite of the heat amount generated by the energy deposition of the secondary particles provided by the impact of the primary proton beam onto the target, • definition of the radiation tolerance, • integration of the target. M. Dracos, EUROnu-WP2
Power Supply for horn pulsing (major issue) values considered by CERN M. Dracos, EUROnu-WP2
3 Solutions proposed by ABB schematic versions at the capacitors ends option 1 at the capacitors ends option 2 in the charge option 3 s M. Dracos, EUROnu-WP2
q13 Sensitivity simulation inputs • Detector: • Water Cerenkov • 440 kt • at Fréjus (130 km from CERN) • Run: • 2 years with positive focusing. • 8 years with negative focusing. • Computed with dCP=0 (standard benchmark) and q13 = 0 • parameter… • Dm23 = 2.5 10-3eV2 • Dm12 = 7.1 10-5eV2 • sin2(2q23) =1 • sin2(2q12) =0.8 M. Dracos, EUROnu-WP2
Sensitivity 3.5GeV A.Cazes thesis Dm223 90%CL 95%CL 99%CL 10-2 Minimum: q13= 1.2° (90%CL) 10-3 10-4 sin22q13 10-1 10-3 10-2 no strong dependence on proton energy for 2.2<p<5 GeV M. Dracos, EUROnu-WP2
Present Collectors In operation (120 GeV) In operation (8 GeV) completed (12 GeV) CERN horn prototype for SPL Super-Beam (3.5 GeV) In operation (400 GeV) MiniBooNE NUMI CNGS K2K M. Dracos, EUROnu-WP2
Horn prototype • For the horn skin AA 6082-T6 / (AlMgSi1) is an acceptable compromise between the 4 main characteristics: • Mechanical properties • Welding abilities • Electrical properties • Resistance to corrosion • Same for CNGS …but Al not compatible with Mercury! • tests done with: 30 kA and 1 Hz, pulse 100 ms long • new tests to be done with 50 Hz Electrical and water connections M. Dracos, EUROnu-WP2
protons protons protons protons minimize power dissipation and radiation problems (pulser problems remain as before) 2.5 m use the advantage of the small horn size New ideas 2.5 m same decay tunnel Ø 3 m to be studied in EURO • 2 options (only one pulser): • send at the same time 1 MW per target/horn system • send 4 MW/system every 50/4 Hz possibility to use solid target? M. Dracos, EUROnu-WP2
superconducting wire (1 mm Ø) in superfluid He, DC power supply use a cryogenic horn (toroidal coil) New (crazy) ideas blow gas He to avoid quenching problems • No problem with power supply (pulser no more needed) • Proton compressor no more needed to be studied in EURO M. Dracos, EUROnu-WP2
Conclusions • LP-SPL already approved, HP-SPL possible before 2020. • Many studies needed on targets. • Collector studies are necessary to increase the system lifetime. • Target/horn integration to be considered since the beginning. • New studies have started in the framework of EURO FP7 project. • New ideas are welcome… M. Dracos, EUROnu-WP2
End M. Dracos, EUROnu-WP2
CHOOZ excluded 10-1 CNGS combined Sin22q13 Double CHOOZ Beta Beam Disappearance 10-2 T2K SPL 5y BNL SPL 1y+4y 10-3 SPL 2y+8y Beta Beam (5y+5y) 10-4 100 -150 -100 -50 -0 50 150 dCP (deg.) Comparisons M. Dracos, EUROnu-WP2
CERN horn prototype cooling system Current of 300 kA p Protons To decay channel B = 0 Hg Target B1/R initial design satisfying both, neutrino factory and super-beam M. Dracos, EUROnu-WP2
Decay Tunnel Flux vs decay tunnel length (2.2 GeV option) short decay tunnel M. Dracos, EUROnu-WP2