Super-beam work package in the Euro ν DS: status and plans

1. Super-beam work package in the EuroνDS:status and plans Marco Zito Dapnia-Saclay On behalf of the SB wp team IDS CERN 30/3/2007 Thanks to C. Densham and M. Dracos for providing materials! Marco Zito

2. Outline • Superbeam : status • About this workpackage • Focusing on the most challenging/crucial problems : • The target • The collector • The target/collector integration • Neutrino beam simulation • Deliverable: a CDR for the Superbeam! • Participating institutes: IN2P3, CEA, CCLRC, Cracow U. of Technology + other additional partners (inside and outside Europe) Marco Zito

3. Super-Beams projects Cf talks by M.Bishai and N. Saoulidou projet BNL projet Fermilab Marco Zito

4. Linac to RCS RCS to MLF Extraction from RCS Linac from down stream neutrino decay volume MR tunnel Linac from front end Marco Zito Status 4

5. Work at RAL on T2K target, windows for 750 kW operation -> Beam dump designed for 3-4 MW operation-> Continue studies for 3-4 MW operation e.g. beam window, target limits Helium cooling of target Target within magnetic horn Marco Zito

6. MR (2 #bunch, 2 Rep. Rate) MR (2 #bunch, 1.5 Rep. Rate) n commissioning n line const. n phys run MR (2 #bunch) RCS Power MR Power (Default) Superbeam in Japan : T2K phase 2 3 400MeV LINAC from FY2011 2 Beam Power (MW) T2K needs Serious Upgrade 1 0 2008 2009 2010 2011 2012 Japanese Fiscal Year (Apr-Mar) Marco Zito

7. What Euroν DS Superbeam is about-1 • Consider as baseline the SPL to Frejus concept MEMPHYS Far detector R/D, feasibility, etc. is covered by the Laguna DS Marco Zito

8. What Euroν DS Superbeam is about-2 • Proton driver and target : many issues in common between Super-beam and NF • Decide to join forces and tackle these problems in this WP • The NF WP will focus on the muon front-end • The conclusion of this WP will then be incorporated in the SB and NF CDR’s Marco Zito

9. Super-Beam Focus of this DS ~300 MeV n m Neutrinos small contamination from ne (no K at 2 GeV!) Marco Zito

10. SPL • See presentation by Roland Garoby • CDR for SPL already available • Refinements, R/D, further studies in other frameworks (HIPPI, IA …) • Changes to this proton-driver design only from the optimization of the target and collection or from the physics and detector studies Marco Zito

11. CERN Super-Beam (SPL) recent document Marco Zito

12. R. Garoby @NuFact06 CERN Super-Beam (SPL) Possible energy upgrade to 5 GeV could be the subject of a 3rd CDR (CDR3) Marco Zito

13. 5 GeV version of the SPL R. Garoby @NuFact06 Increasing the energy of the SPL (CDR2) is obtained by adding 105 m of b=1 superconducting accelerating structures and 14 klystrons [704 MHz – 5 MW]. SPL (CDR3) characteristics Marco Zito

14. The target • 300-1000 J cm-3/pulse • Severe problems from : sudden heating, stress, activation • Safety issues ! • Baseline for NF is mercury jet, for superbeam is solid target • Extremely difficult problem : need to pursue two approaches : • Liquid metal target (Merit experiment) • Solid target (extensive R/D program at CCLRC) • Envisage alternative solutions Marco Zito

15. MERIT • MERIT experiment will test Hg jet in 15-T solenoid • 24 GeV proton beam from CERN PS • scheduled Spring 2007 15-T solenoid during tests at MIT Hg delivery and containment system under construction at ORNL. Integration tests scheduled this Fall at MIT. Marco Zito

16. Marco Zito

17. Solid target study programme at RAL • Future Programme • Continue wire tests with Tungsten and Graphite. • Continue modelling computations. • VISAR measurements to asses the properties of tungsten, and any changes, during the wire tests. (Effect of thermal shock.) • Tests with a proton beam to confirm wire tests and VISAR measurements – but limited number of pulses. • Radiation damage studies. • Test alloys of tungsten. • Design & build a model of the target bar system. • Design the solenoid. • Design and cost the complete target station including the beam dump. Marco Zito

18. Target Parameters Proton Beam pulsed 50 Hz pulse length ~40 s energy ~10 GeV average power ~4 MW Target (not a stopping target) mean power dissipation 1 MW energy dissipated/pulse 20 kJ (50 Hz) energy density 300 J cm-3 (50 Hz) beam 2 cm 20 cm R. Bennett @NUFact06 Marco Zito

19. R. Bennett @NUFact06 Test wire, 0.5 mm Φ Pulsed Power Supply. 0-60 kV; 0-10000 A 100 ns rise and fall time 800 ns flat top Repetition rate 50 Hz or sub-multiples of 2 Coaxial wires Vacuum chamber, 2x10-7 -1x10-6 mbar Schematic circuit diagram of the wire test equipment Marco Zito

20. R. Bennett @NUFact06 Marco Zito

21. Some Results of 0.5 mm diameter wires Material Lngth cm Pulse Current A Pulse Temp. K Max. Temp K Rep Rate Hz No. of pulses to failure Beam Power MW Target dia cm Tantalum 4 3000 60 1800 12.5 0.2x106 Tantalum is not a very good material – too weak at high temperatures. Tungsten Broke when increased to 7200A (2200K) 3 4900 100 2000 12.5 >3.4x106 2 4 2 3 Stuck to top Cu connector 3 6400 170 1900 6.25 >1.6x106 4 8 2 3 Not broken; still pulsing 2.5 5560 5840 130 140 1900 2050 12.5 12.5 4.2x106 +PLUS+ >6.5x106 3 6 - 2 3 - R. Bennett @NUFact06 Equivalent Target “Equivalent Target”: This shows the equivalent beam power (MW) and target radius (cm) in a real target for the same stress in the test wire. Assumes a parabolic beam distribution and 4 micro-pulses per macro-pulse of 30 s. Marco Zito

22. Schematic arrangement of the chain mechanism for the target bars Target Bar Chain Links Chain Sprocket for the front of the bars Chain Sprocket for the rear of the bars R. Bennett @NUFact06 Marco Zito

23. A new Nufact/SuperBeam target concept being studied at RAL: fluidised jet of particles C. Densham • A Fluidised jet of tungsten or tantalum particles in He could be used as a neutrino factory target • It could have high Z + high volume density • Can be effectively removed from the solenoid field hence reducing the pion reabsorption • Can be replenished as particles wear out • Particles can be easily cooled (in an external fluidised bed) Marco Zito

24. Attractions of fluidised target concept C. Densham • Combines the advantages of the solid target with those of the liquid target • Solid displacement without moving parts • Shock waves constrained within the material(no cavitation, no splashing) • Highly effective cooling of the target material • Favourable material geometry for the stress waves • Target easily replenishedand reasonably safely contained • Nothing else on the beam line apart from the target material • BUT: Is it technically feasible? - Study needed www.tudelft.nl Marco Zito

25. Outline Targets Programme • Results of MERIT experiment at CERN eagerly anticipated. This will answer many technical questions regarding liquid metal jet targets and will inform future Nufact targets programme • Continue solid target studies • Continue fluidised particle jet target studies • Begin studies of target integration with collection system both for Nufact (solenoid) and for SuperBeam (magnetic horn) • Important synergies with R/D in US labs Marco Zito

26. The collector • Focus on the magnetic horn collection method • Initial design at CERN followed by optimization and redesign • Currents: 300 kA (horn) and 600kA (reflector) • Horn : 3mm to minimize energy deposition • 50 Hz (vs a few Hz up to now) • Longevity in a high power beam • Large em wave, thermo-mechanical stress, vibrations, fatigue, radiation damage Marco Zito

27. Collector • Main challenges: • 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. Marco Zito

28. Collectors M. Dracos horns In operation In operation completed Or solenoid (SB) built MiniBooNE Marco Zito NUMI CNGS K2K

29. Previous Studies • S. Gilardoni: Horn for Neutrino Factory and comparison with a solenoid • http://doc.cern.ch/archive/electronic/cern/preprints/thesis/thesis-2004-046.pdf • http://newbeams.in2p3.fr/talks/gilardoni.ppt • A. Cazes: Horn for SPL • http://tel.ccsd.cnrs.fr/tel-00008775/en/ • http://slap.web.cern.ch/slap/NuFact/NuFact/nf142.pdf • http://slap.web.cern.ch/slap/NuFact/NuFact/nf-138.pdf Marco Zito

30. Focusing system: magnetic horn M. Dracos Current of 300 kA p To decay channel Protons B = 0 Hg Target B1/R Marco Zito

31. Horn prototype ready for tests M. Dracos Marco Zito

32. Proposed design M. Dracos Particle at target 2.2 GeV protons In collaboration with LAL Marco Zito

33. 2.2 GeV proton beam : <pp> = 405MeV/c <qp> = 60° 3.5 GeV proton beam : <pp> = 492MeV/c <qp> = 55° New Geometry M. Dracos I = 300 kAmp I = 300 kAmp r(m) r(m) 4 cm 4 cm 30 cm z(m) 30 cm z(m) Marco Zito

34. Power Supply for horn pulsing (major issue) M. Dracos values considered by CERN Marco Zito

35. the power supply M. Dracos Due to the high price go to a modular system and increase small by small the current Marco Zito

36. Neutrino Beam simulation • Needed to optimize the target, collector, decay tunnel • Use modern tools (GEANT 4) and recent data (HARP) • Input to the physics work package for the performance evaluation • Need to develop in synergy with similar studies in existing SB and in the IDS community Marco Zito

37. "Physics" studies to be restarted M. Dracos P (kW) corne 2 z (cm) energy deposition z (cm) corne Marco Zito

38. Sensitivity 3.5GeV Preliminary 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 Marco Zito

39. Conclusions • SuperBeam work package of the Euroν DS is focusing on the key issues for this project • The SPL to Fréjus project is the baseline • The SPL CDR2 study is an excellent starting point for the proton driver • Feasibility and conceptual solutions for the target and collector (horn) will be studied • A strong European collaboration is ready to contribute to this field Marco Zito

40. R. Garoby @NuFact06 Scenario for accumulation and compression (2/13) Accumulator [120 ns pulses - 60 ns gaps] SPL beam [42 bunches - 21 gaps] Compressor [120 ns bunch - V(h=3) = 4 MV] Target [2 ns bunches – 6 times] Marco Zito

41. R. Garoby @NuFact06 Scenario for accumulation and compression (4/13) Bunch characteristics at injection in the compressor Bunch characteristics at ejection to the target Marco Zito

42. Focussing power corne 2 (réflecteur) corne focalisation CNGS Marco Zito

43. Result of a geological survey: • Very good rock quality • 3-4 shafts Φ=70m (250k m3 each, fiducial 150KT) • 5 years excavation • 80 ME x N(shaft) Memphys PMT R/D ongoing A possible timeline 2010 decisions for cavity excavation, SPL and Eurisol Marco Zito

44. Marco Zito

45. K. McDonald @ISS, Irvine Marco Zito

46. K. McDonald @ISS, Irvine Marco Zito

47. K. McDonald @ISS, Irvine Marco Zito

48. Flux summary, 2.2 GeV Decay tunnel :20m Decay tunnel :80m Marco Zito

49. Flux summary, 3.5 GeV Decay tunnel :20m Decay tunnel :80m Marco Zito

50. q13 Sensitivity • Use Mauro Mezzetto code. • detector: • Water Cerenkov • 440 kt • at Fréjus (130 km from CERN) • Run: • 2 years with positive focussing. • 8 years with negative focussing. • 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 Marco Zito