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JET Scientific Programme 



Phase I 



Ohmic Heating Phase 



Hydrogen or Deuterium Plasmas 



Phase MA 



Additional Heating Studies 



10 MW of Neutral Beam Heating 



6 MW of Radio Frequency Heating 



Hydrogen or Deuterium Plasmas 



Phase III 



Full Power Optimisation Studies with full 



remote handling 



10 f\/IW of Neutral Beam Heating 



15 M\N of Radio Frequency Healing 



Deutenun 



Phase IV 



Full Power Operation 



Deuterium-Tritium Plasmas 



The aim of the JET proiect is to obtain a plasma with a size, 

 density and temperature comparable to the values needed 

 in an eventual power producing reactor 



During the four phases of the programme the power 

 available for heating the plasma will be increased in stages 

 The first phase, until the end of 1984, was limited to heating 

 the plasma by passing a large current through either 

 hydrogen or deuterium gases Over the next few years 

 increasing amounts of radio-frequency and neutral beam 

 iniection heating will be added 



During the final phase of operation a mixture of deutenum 

 and tritium will be used so that abundant fusion reactions will 

 be produced 



As a result of these reactions there will be considerable self 

 heating of the plasma Also high energy neutrons will be 

 produced that will make the structure radioactive 



Remote Handling 



Because the machine will be ^~ 



radio-active during the final stages of ^ 

 the programmes, remote handling 

 systems are being installed for 

 ; of the machine 



Protection is provided by the thick 

 concrete walls, ceiling and floor of the 

 Torus Hall The mam access door to 

 Torus Hall weighs 400 tonnes 



JET Results 



JET has been designed to produce pulses once every ten 

 minutes Each pulse lasting tor about 25 seconds with 

 plasma currents up to 5 million amperes 

 For reactor conditions temperatures m excess of 100 million 

 degrees Celsius will be needed. In addition the energy 

 losses from the plasma must be reduced to a sufficiently low 



level A measure of how well this has been accomplished is 

 given by the Lawson Criterion or confinement parameter-the 

 product of fuel density (number of particles per metre cube) 

 and energy confinement lime (Ihe lime it would lake for the 

 plasma energy to decrease by a half) 



The values needed in a r 



These are the full design values for phase one operation and 

 have established JET as the most powerful tokamak in the 

 < 3EA world. 



