Next generation of ν beams Challenges Ahead I. Efthymiopoulos - CERN LAGUNA Workshp Aussois, France, September 8,2010 what it takes to design and construct a MW class Super-beam or Neutrino Factory First  event from OPERA/CNGS EDMS Id:

Neutrino beams I.Efthymiopoulos-CERN, Sep 8,2010  Three “conventional” ν beams operational today Overview CNGS - 0.3MW sustained operation 0.5MW if in dedicated mode CN2?? MW “ultimate”, requires SPS and injector upgrade HP-CN2?? - 4MW operation requires if HP-SPL + HP-PS’ NUMI/MINOS - 0.3MW sustained operation NUMI/NOVA MW upgrade (~2013) LBNE/DUSEL - 2MW operation requires Project-X T2K - 0.1MW operation so far T2K MW gradually ~2011 T2K MW designed operation after some years CERN FNAL JPARC 2

Neutrino beams I.Efthymiopoulos-CERN, Sep 8,2010  Conventional neutrino beam  Super-beam if proton beam power >1MW Super beams 43.4m 100m 1095m18m5m 67m 2.7m TBID p + C  (interactions)  π +, K +  (decay)  μ + + ν μ 3

Neutrino beams I.Efthymiopoulos-CERN, Sep 8,2010  IDS-NF baseline Neutrino factory p + C (interactions)  μ ± (capture, accelerate, store, decay) )  ν μ, ν e  Typically a MMW system for the target and front-end 4

Neutrino beams I.Efthymiopoulos-CERN, Sep 8,2010  Experience shows that DESIGNING and OPERATING a high- power neutrino beam facility is rather challenging  Key issues where present R&D effort is concentrated:  Target and Target chamber designs  SB: Secondary beam elements – NF: Front-end system SB: horns – NF: cooling channel, RF & absorbers  SB: Hadron stop – NF: Beam dump  SB: Decay tunnel – NF: Storage ring  Neutrino beam monitoring & Near detector Challenges 5

Neutrino beams - Targetry  Targets are key elements in the production of neutrino beams I.Efthymiopoulos-CERN, Sep 8,2010 Overview High-power primary beam (protons) Target Secondaries π (for Super ν beams) μ (for Neutrino Factory or Muon Collider)  High-power targetry challenges  Thermal management : target melting (solid targets) – Target vaporization (liquid)  Radiation Radiation protection - induced radiation - remote handling  Thermal shock Beam induced pressure waves  Choice of materials  Material Choices  Solid targets Fixed Moving Particle beds  Liquid  Hybrid  Particle beds in liquids  Pneumatic driven particles Where is the limit for solid targets? 6

Target systems I.Efthymiopoulos-CERN, Sep 8,2010 Present facilities CNGS : graphite rods 4(5)mm ∅, air cooled T2K: graphite, forced He cooling NUMI: graphite, water cooling 7

Target systems – future facilities I.Efthymiopoulos-CERN, Sep 8,2010 Neutrino Factory – MMW target station Iron Plug Proton Beam Nozzle Tube SC-1 SC-2 SC-3SC-4 SC-5 Window Mercury Drains Mercury Pool Water-cooled Tungsten Shield Mercury Jet Resistive Magnets Neutrino Factory Study 2 Target Concept ORNL/VG Mar2009 Splash Mitigator V.Graves - ORNL 8

The MERIT experiment I.Efthymiopoulos-CERN, Sep 8,2010 MMW target concept – proof-of-principle experiment Syringe Pump Secondary Containment Jet Chamber Proton Beam Solenoid 9

The MERIT Experiment I.Efthymiopoulos-CERN, Sep 8,2010  Jet surface smoothens out with the increased magnetic field Setup Experimental CERN Hg-jet stabilization by magnetic field 0T Jet velocity: 15m/s 10T 10

The MERIT Experiment I.Efthymiopoulos-CERN, Sep 8,2010  Hg-jet disruption mitigated by magnetic field  20 m/s jet operation allows up to 70Hz operation with beam Key results Hg-jet 4×10 12 p, 10T fied  Disruption threshold: >4×10 12 GeV, 10T field  115kJ pulse containment demonstrated  8 MW capability demonstrated 11

The MERIT Experiment I.Efthymiopoulos-CERN, Sep 8,2010  The MERIT experiment successfully demonstrated the target concept of a liquid target (Hg-jet) for a Neutrino Factory/Muon Collider setup HOWEVER….  Going from the proof-of-principle to a real implementation of a target station for a 4MW beam operation requires additional R&D and engineering design  Key issues:  Radiation : to materials, shielding, access conditions, environment  Remote handling : maintenance and early repair operations  Ventilation, access  Dismantling Summary 12

Target station – Future facilities I.Efthymiopoulos-CERN, Sep 8,2010 Neutrino Factory – MMW target station P. Spampinato - ORNL 13

Target station – Future facilities I.Efthymiopoulos-CERN, Sep 8,2010 LBNE – super beam design P.Hurh - FNAL 14

Target station – Future facilities  Designed for Mega-W proton beam power  Massive shielding to acceess the beam elements I.Efthymiopoulos-CERN, Sep 8, T2K target station Beam elements Shielding (movable)

Target station - Remote handling I.Efthymiopoulos-CERN, Sep 8,2010 LBNE – target station hot cell P.Hurh - FNAL 16

Target station - Remote handling I.Efthymiopoulos-CERN, Sep 8,2010  Remote handling operations for target exchange T2K facility C.Densham - RAL 17

Focusing elements I.Efthymiopoulos-CERN, Sep 8,2010  Material  Few materials to avoid galvanic corrosion  Al typically he best choice  Radiation  Electrical issues  Cooling (water)  Mechanical stresses – pulsing  Alignment precision  Exchange and maintenance procedures Design issues - horns CNGS horn 18

Decay pipe I.Efthymiopoulos-CERN, Sep 8,2010  Shielding & cooling(?) along the decay pipe  T2K: He container 19 T2K decay pipe

Hadron stop – Beam dump I.Efthymiopoulos-CERN, Sep 8,  They both take substantial amount of the beam power  non trivial to design !!!  Cooling and RP issues the main worries T2K Hadron Stop T. Ishida – JPARC T. Davonne - RAL Hg-Jet/Beam dump impact

Technical challenges I.Efthymiopoulos-CERN, Sep 8,  Civil engineering – big slopes, depth for near detector  Installation/maintenance of equipment  Beam instrumentation  Beam collimators (around target area)  Alignment (installation & beam-based methods)  Ventilation  Air activation, tritium  Access  Cranes – remote handling  Decommissioning  … and think of early repairs !!! To complete the picture

Summary I.Efthymiopoulos-CERN, Sep 8,  The design of neutrino beams from Mega-Watt proton beam sources is very challenging pushing materials and components to the limits  Experience exists from the design and operation of conventional neutrino beams over the last years at CERN (CNGS), NUMI(FNAL), JPARC(T2K) which could easily operate at 0.75MW of proton beam power  The T2K facility designed to accept up to 4-MW of primary beam power will hopefully grow up in intensity reaching the Mega-W region in few years, thus would provide useful information for the design of other neutrino superbeams presently under consideration