JET

Figure 1:Aerial view of JET - Culham (UK)

The History of JET
JET Parameters
JET Milestones
JET Scientific Achievements
JET Facilities under EFDA
JET Objectives
JET Experimental Campaigns

The history of JET

The JET Joint Undertaking was established in June 1978 and the JET machine started operating in 1983. It was the first fusion facility in the world to achieve a significant production of controlled fusion power (nearly 2MW) with a Deuterium–Tritium experiment in 1991.
JET furthered fusion science well beyond its original goals and evolved into a physics and technology basis for preparing ITER, the "next step" towards a reactor. JET has made fundamental contributions to the ITER design and provided key data for the definition of the size, heating requirements and operating conditions of ITER. During 1997 JET set three world records: 22 MJ of fusion energy in one pulse, 16 MW of peak fusion power and a 65% ratio of fusion power produced to total input power. In Spring 1998 the fully remote handling installation of a new divertor (a major in–vessel component) was successfully completed on time, demonstrating another technology vital for both ITER and a future fusion power plant.
Since 1^st January 2000, the overall implementation and co–ordination of further scientific exploitation is carried out under EFDA, the European Fusion Development Agreement. In this new scheme, the European laboratories play key roles, with their physicists conducting the experimental campaigns and their engineers implementing and leading the projects of enhancement of the facilities. As for the operation and maintenance of the JET facilities, it is conducted on behalf of EFDA by the UK Atomic Energy Authority (UKAEA), into the custody of whom the ownership of the facilities was transferred after the closure of the Joint Undertaking.

Figure 2:JET - In the Torus Hall

Figure 3:JET Inside

JET Parameters

Plasma Major Radius	2.96 m
Plasma Minor Radius	1.25 m (horizontal) 2.10 m (vertical)
Toroidal Magnetic Field (on Plasma axis)	3.45 t
Plasma Volume	~ 100 m3
Plasma Current	Circular Plasma 3.2 MA D-Shape Plasma 4.8 MA
Flat-top pulse length	20 s
Volt-seconds to drive plasma current	34 Vs
Additional heating power	25 MW

Figure 4:JET Machine

JET Milestones

1973	The Design Team starts working on JET.
1977	The Culham site (UK) is chosen.
1978	Start of the JET Joint Undertaking.
1979	The works at the site start.
1983	JET operations start.
1985	JET achieves a plasma current of 5 MA.
1988	JET achieves a plasma current of 7 MA.
1991	Preliminary Tritium Experiment, first production of D-T fusion power in a magnetic fusion device (1.7 MW).
1993	Installation of Mark I divertor.
1995	Installation of Mark II divertor.
1997	D-T Experiments - World Record of 16 MW power.
1999	The Joint Undertaking ends.
2000 - 2001	First four experimental Campaigns under EFDA.
2001	The machine is shut down and enhancements implemented.
2002 - 2003	Further experimental campaigns under EFDA.

Figure 5:

JET Scientific Achievements

The JET programme has extended into a new space. Plasma currents of up to 7 MA have been achieved well beyond the design value of 4.8 MA. The understanding of the plasma behaviour has progressed significantly. Physics phenomena such as instabilities, disruptions, confinement and transport mechanisms have been analyzed and better understood. High performance diagnostic systems have been developed allowing progress in accurate measurements.
New plasma confinement modes have been confirmed. Steady state plasmas have been maintained for several seconds in various high performance regions.
Engineering solutions, such as the divertor and alternative materials (Beryllium and Carbon) have been studied to decrease the level of impurity in the plasma. New engineering solutions have been conceived and adopted, resulting in beneficial spin-offs for other disciplines.
Plasmas close to reactor conditions have been and continue to be studied, contributing to the preparation of a solid basis to the ITER operations.
And finally JET has also helped in training the physicists and the engineers who are now at the heart of the effort to build ITER, the "next step" machine and prepare its operation.

Figure 6:Remote Handling at JET

JET Facilities under EFDA

The use of the JET facilities under EFDA since 1 January 2000 has reinforced cooperation between the European laboratories involved in fusion research.
The experimental programme on JET is organized in campaigns, with scientists coming to Culham (UK) for limited periods. Most of the complementary work, related to the preparation of experiments, data analysis and modelling, is conducted from the home laboratories. The scientific work is organized in Task Forces under the coordination of Task Force Leaders belonging to the European laboratories associated to EFDA.
The local host, UKAEA, is responsible for the operation, maintenance and safety of the JET facilities.
This new method of working has been successful during the 2000-2001 Campaigns, with more than 300 European scientists and several tens of non–Europeans involved. The preparation of the 2002 experimental campaigns has triggered a high degree of scientific interest in the fusion laboratories, as demonstrated by the submitted 333 scientific proposals for the 100 experimental days foreseen!
This same spirit animated the first enhancement projects initiated under EFDA in the year 2000. Following similar principles to those applied in the scientific programme, Project Leaders belonging to European laboratories lead decentralized teams for the design and procurement of the enhancements. A strong link is established with the JET operator, UKAEA, responsible for the installation and commissioning of the enhancements.
Through the success of the first experimental campaigns, the successful achievement of the first enhancement projects and the continuation of medium term enhancements, the European fusion laboratories have demonstrated a strong capability to work efficiently together, sharing efforts and responsibilities and optimising the collective use of their various competencies.
This organization anticipates a possible cooperative scheme for the scientific exploitation of ITER.

JET Objectives

The aim of the key action "controlled thermonuclear fusion" is to further develop the necessary basis for the possible construction of an experimental reactor (the "Next Step": ITER), with the objective of demonstrating the scientific and technological feasibility of fusion power production as well as its potential safety and environmental benefits. In the longer term, it will prepare for the development of a demonstration reactor and then a prototype reactor.
To establish the physics basis for a Next Step such as ITER, several devices in the EU contribute, including JET. A co-ordination among these activities is therefore necessary and is performed by EFDA.
The collective use of the JET facilities provides a unique contribution to the consolidation of the scientific basis in plasma physics and plasma engineering and to the demonstration of high performance in operational modes relevant to the objectives and configuration of ITER.
In addition operation of the JET Facilities contributes to the provision of the engineering basis of several Next Step technology issues, in particular on defining the operating conditions of plasma facing materials and components, and in testing advances in remote handling and tritium technology.

JET Experimental Campaigns 2003 / 2004

Campaign C8: 2 March 2003 to 16 April 2003
Campaign C9: 2 May 2003 to 16 May 2003
Campaign C10 - HP1 (High Power): 17 August 2003 to 16 September 2003
Campaign C11 - TTE (Tritium Trace Experiment): 21 September 2003 to 31October 2003
Campaign C12 - HP2 (High Power): 23 November 2003 to 19 December 2003
Campaign C13: 11 January 2004 to 30 January 2004
Campaign C14: 8 February 2004 to 27 February 2004

For more information see the detailed JET 2004 Workprogramme C12 - C14 Experiments' Schedule

For additional information please visit: http://www.jet.efda.org/index.html