The International Workshop on Thin Films. Padova 9-12 Oct of slides Present Status of the World- wide Fusion Programme and possible applications of superconducting Accelerators. Roberto Andreani

The International Workshop on Thin Films. Padova 9-12 Oct of slides What is fusion?

The International Workshop on Thin Films. Padova 9-12 Oct of slides Why Fusion?

The International Workshop on Thin Films. Padova 9-12 Oct of slides The Magnetic Confinement

The International Workshop on Thin Films. Padova 9-12 Oct of slides Fusion: a Breeding Reactor

The International Workshop on Thin Films. Padova 9-12 Oct of slides JET

The International Workshop on Thin Films. Padova 9-12 Oct of slides From JET to ITER 16 MW power produced. 1s 500 MW,400s,Q = 10

The International Workshop on Thin Films. Padova 9-12 Oct of slides Progress in fusion physics understanding

The International Workshop on Thin Films. Padova 9-12 Oct of slides

The International Workshop on Thin Films. Padova 9-12 Oct of slides Major Technological Problems of ITER Superconducting Magnets (Nb 3 Sn); Plasma Facing components (Be→W); Remote Handling; Structural Materials (St.St.→Martensitic).

The International Workshop on Thin Films. Padova 9-12 Oct of slides Interaction of 14 MeV neutrons with the structural materials Atoms displacement from their positions in the lattice→ Hardening and brittleness. 1 MW/m 2 a = 10 dpa. Reactor first wall: ~ 2 MW/m 2 → 20 dpa/a Transmutation reactions: Hydrogen and helium produced→Swelling and brittleness. A cumulative effect is the change in the Ductile to Brittle Transition Temperature (DBTT).

The International Workshop on Thin Films. Padova 9-12 Oct of slides Displacement in the DBTT. ( Measured after irradiations in fission reactors)

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIF (International Fusion Materials Irradiation facility) An intense source of 14 MeV neutrons (10 18 n/s). 50 dpa/a in 0.5 l volume. 20 dpa/a in 6 l. To study the effect of 14 MeV neutrons on fusion reactor materials. So far only <10 12 n/s, 14 MeV sources available. Only qualitative probing of the effects of 14 Mev neutrons on materials possible. IFMIF experimentation, besides direct results, will also allow correlating the large amount of existing data collected in irradiations with fission neutrons or ion beams.

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIF

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIF. Target System. Schematic view Mission : Obtain stable and high speed Li flow during 10 MW D + beam loading D + Accelerator Liquid Li Target Neutrons (~10 17 n/s) Li Free Surface EMP D + Beam (10MW) Specimens

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIF Time Schedule and Cost The IFMIF programme foresees two phases: -Engineering Validation, Engineering Design Activities (EVEDA). Duration: 6 years. -Construction Phase: 7 years. EU is entering the EVEDA phase in the framework of an Agreement of collaboration with Japan. Cost of the EVEDA phase: 150 MEuro ( 65 % EU, 35 % Japan) Estimated Cost of the Construction Phase: 800 MEuro. (In the framework of an international collaboration yet to be established)

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIF NC Accelerators

The International Workshop on Thin Films. Padova 9-12 Oct of slides Main NC Accelerator Characteristics ECR Ion Source, D + 95 KeV, 140 mA. Low Energy Beam transport. Three sections 4-vanes RFQ: 95 KeV to 5 MeV, 125 mA. Matching Section. 10 Alvarez type DTL tanks: 5 MeV to 40 MeV, 125 mA. Length: 30.3 m: ave.: 1.15 MV/m. Beam Centroid (20x5 cm cross section): Time Averaged Position Tolerance on Target: ± 1 mm 12-13, 1 MW, cw, 175 MHz RF Generators 18.5 MW electric power from the network required to power each accelerator.

The International Workshop on Thin Films. Padova 9-12 Oct of slides IFMIFAccelerator System Baseline RF Power System 12 Required, 1MW CW, 175 MHz High Energy Beam Transport (HEBT) Drift Tube Linac (DTL) CW 175 MHz, 10 Tanks, 30.3 m, 40MeV Matching Section (MS) 2-single Gap Cavities, 4 Quadrupoles, 0.66 m long Radio Frequency Quadrupole (RFQ) CW 175 MHz, 12.5 m long, water cooled, 5 MeV Ion Injector CW ECR, Source, 140 mA D +, 95 keV, Magnetic LEBT to RFQ Large Bore Quad & Dipoles, 55 meters long Realization of stable steady operation: lifetime: 1,000hr 。 Stable operation Contact-free beam diagnostic technology Availability >8 ８ % Hands-on maintenance Shaping beam footprint Accelerator

The International Workshop on Thin Films. Padova 9-12 Oct of slides Choice of Accelerator Within the end of the year an investigation will be conducted to establish whether a solution with two accelerators, including superconducting DTLs, would offer definite advantages for IFMIF. For the normal conducting design: - ECR ion source, D + beam. -nc RFQ, 5 MeV. Fed by ~ 1.6 MW RF power, 175MHz. -The nc DTLs, 5 to 40 MeV, absorb: 10x710 kW RF power= 7.1 MW. -Total RF power: 8.7 MW. ~ 18.6 MW from network. -Length of the DTLs: 30.3 m. Beam power: A x 40 MeV = 5 MW

The International Workshop on Thin Films. Padova 9-12 Oct of slides A preliminary superconducting design has been considered: -ECR ion source and nc RFQ are the same as for the nc solution -one nc DTL, 5 to 10 MeV. Fed by ~ 0.7 MW RF power. -7 sc DTL, Nb at 4.2 K, 10 to 40 MeV. (1x x450) kW = 3.4 MW RF power. -Total RF power: 5.7 MW. ~11.4 MW from network. -Length of the DTL: ~ 9 m. -Cryogenic power: ~ 700 W MW from the network A preliminary superconducting design has been considered: -ECR ion source and nc RFQ are the same as for the nc solution -one nc DTL, 5 to 10 MeV. Fed by ~ 0.7 MW RF power. -7 sc DTL, Nb at 4.2 K, 10 to 40 MeV. (1x x450) kW = 3.4 MW RF power. -Total RF power: 5.7 MW. ~11.4 MW from network. -Length of the DTL: ~ 9 m. -Cryogenic power: ~ 700 W MW from the network

The International Workshop on Thin Films. Padova 9-12 Oct of slides SC DTL. ( Preliminary Conceptual design with seven s/c cavities) Dia.= 1600 mm L = ~ 9 m

The International Workshop on Thin Films. Padova 9-12 Oct of slides Proposed Cross-Bar, H mode, superconducting cavity for IFMIF Diameter: 550 mm

The International Workshop on Thin Films. Padova 9-12 Oct of slides Qualitative Evaluation of the Superconducting Solution. Advantages: -Maximum field gradient limited only by H in the superconducting walls and E max (potentially very good vacuum quality). No limitation due to cooling. Energy/m about 3 times. Length of the accelerator about 50%. -Capital cost saving: - Linear Size of the building. But cryogenic system? - Number of RF generators. -Operational costs. Overall electric energy from network. -Larger aperture of the drift tubes  low wake fields, no measurable impact on RF losses of the smaller shunt impedance  lower activation (< 1 W/m beam loss needed). Disadvantages or doubts: -Cryogenic system, capital and operating cost. Space requirement. -Time schedule for construction of the sc DTLs. -Reliability of the technology, to be assessed. -Maintenance problems. Access.

The International Workshop on Thin Films. Padova 9-12 Oct of slides Preliminary evaluations of the costs (to be assessed by an Ad Hoc WG). 20 years operation. 2 Accelerators (Complete) Capital Cost MEuro Operating costs MEuro/year NC solution31579 SC Solution24572 Saving707