1. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 RISERVA Verticale

2. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 The idea is to form an ULART by producing a Screw Pinch that will be destabilized by increasing the longitudinal arc current I e : such a configuration has been obtained for the first time on the TS-3 experiment (Tokyo University) Screw Pinch with longitudinal field B Z toroidal field B safety factor q Pinch = 2 Pinch B Z /L Pinch B Aims of PROTO-SPHERA

3. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 ProtosPhera CATIA Drawing

4. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 Pyrex vacuum vessel MicroWave Interferometry Visible Spectroscopy Cathode 8 conductors for the I e return External coils. Gas Feed Vacuum Pump PROTO-PINCH Experimental Set-Up

5. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 COILS Two groups of PF coils (j PF 2 kA/cm 2 ), each composed by coils connected in series Group 'B' - shape the pinch with constant currents Group 'A' - compress the ST with variable currents

6. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 ST diameter 2R sph =0.7m Toroidal plasma current I p =240kA Aspect ratio A=1.2, elongation =2.35 Similar to the START spherical torus experiment Pinch current I e =60 kA « I tf 200 kA (START centerpost) Main Features

7. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 Cost, Schedule & Size Vessel, including: tiles, supports, Baking system and base 665,000 Design contract 77,000 Subtotal 742,000 Poloidal field coils, including: feedthroughs and cooling system 826,000 Design contract 77,000 Subtotal 903,000 Anode and Cathode, including feedthroughs and cooling system 297,000 Design contract 50,000 Subtotal 347,000 Assembly contract 90,000 Pumps, gas feed & control system 200,000 TOTAL 2,282,000 Power supply: Pinch feeder P904,000 Cathode feeder K102,000 PF feeder A150,000 PF feeder B 31,000 Subtotal 1,187,000 Electrical work contract 93,000 TOTALPower Supply 1,280,000 GRAND TOTAL 3,562,000

8. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 MultiPinch Costs Capital costs of multi-pinch test Load assembly (vessel and electrodes):460000 PF coils and sustaining columns:230000 Power supplies:246000 TOTAL:936000 If, after the multi-pinch test, the decision to build PROTO-SPHERA was taken, between 585000 and 770000 of the capital expenditure of the multi-pinch test could be still put at work. Schedule of multi-pinch test If proposal is accepted in 2003: first plasma by the end of 2005.

9. Associazione Euratom-ENEA sulla Fusione ----- Culham 15-17 September 2003 Panel Question & Answers 1.Is the physics basis for undertaking an experiment as proposed with PROTO-SPHERA adequate? OK, BUT We recommend that a wider range of operation scenarios of and pressure profiles be analyzed... 2)Are the PROTO-PINCH electrode experiments a sufficient technical basis for a reliable electrode operation in PROTO-SPHERA? OK, BUT… are not yet adequate for reliable multi- electrode operation... 3) … In particular, is the proposed size adequate for the purposes of a Concept Exploration Experiment?.. OK 4)How likely is.... to advance the present state of science and technology substantially.. OK 5).. likely to produce new information that is adequate as basis to extrapolate to a SPHERA device that achieves fusion relevant paramenters? OK 6)What diagnostics should be planned in order to properly measure the properties of the PROTO-SPHERA plasma? OK 7)What are the unique contributions of the proposed experiment to the world magnetic fusion programs, and in particular to the European Magnetic Fusion Program during the VI th FP? OK