status of the jet device and planning of task force h in upcoming jet campaigns

J.Ongena -- Status of the JET device in upcoming experimental campaingns PPPL, 27 July 2004

Status of the JET device and planning ofTask Force H inupcoming JET campaigns

J.Ongena, Seminar Princeton Plasma Physics LabPrinceton, New Jersey, USA27 July 2005


JET has World Wide Unique and Unmatched Capabilities

• Burning plasma capability (D-T fuel of ITER, -simulation)

• Size: the closest to ITER, the most relevant physics for consolidating ITER modes of operation (regimes on smaller tokamaks do not always extrapolate to JET)

• Unique technical capabilities: Beryllium - ITER First Wall material; Tritium plant; Remote handling; Real Time Control systems; Diagnostics for burning plasmas

• Scientific exploitation and enhancements under fully collaborative scheme with cross-laboratory integration of scientists, engineers, project managers and administration within a contractual/financial framework


EFDA-JET Workprogrammes 2005/06:Basis for the Scientific Programme

2. Critical issues for ITER

• Characterise discharges in preparation for change of wall/divertor materials

• Characterise disruptions

• Characterise ELM behaviour and edge pedestal in ELMy H-mode

• Measure tritium retention and migration• Establish level of off-axis current

with off-axis NBI and/or MC-ICRH) and quantify degree of rotation achieved with low momentum input

• Quantify physics governing rotational stabilisation of RWMs

• Control core MHD (fishbones) typical of hybrid regimes

• Design tolerable ELMs

(potentially impacting detailed design of ITER components, e.g. first wall, heating & current drive systems, diagnostics..)

• Exploit fully the LH system

• High-level commissioning of the ITER-like ICRH antenna

• Commissioning of the MkII HD divertor

• Commissioning of new/upgraded diagnostics and systems

1. Bring new systems to full performance (divertor, diagnostics, LH launcher and 3dB couplers in early 2006; ITER-like ICRH antenna and conjugate-T after 2006 shutdown)

• High-level commissioning of the ICRH system (3dB couplers and conjugate-T) to full power

• High-level commissioning of the LH system to full power


4. Specific physics issues of direct relevance to ITER (exploiting unique features of JET)

• Explore new burning plasma physics

• Determine transport physics implications for ITER

3. Preparation of ITER operating scenarios

• Extend ELMy H-mode operation at high triangularity to high current

• Extend scaling of ELMy H-mode confinement at low to lowest *, ne* and highest

• Develop a robust steady-state non-inductive scenario with acceptable edge / confinement making full use of real-time control

• Demonstrate portability, fuelling and limits of the hybrid scenario

• Begin to establish reference scenarios ahead of the proposed change of wall/divertor materials

EFDA-JET Workprogrammes 2005/06:Basis for the Scientific Programme


Timetable 2005-2006

Shutdown, Restart and High Level Commissioning 2004/05• Shutdown: started 6 March 2004• Pump-down: performed on 7 July 2005• Restart: first plasma expected beginning September 2005• High Level Commissioning (Restart Contingency): 7 November 2005 (for 2 weeks)

Experimental Programme Schedule end 2005 / 2006 / early 2007• Campaigns C15, C16 and C17 - 21 November to 16 December 2005 (18 S/T days, plus 2 days maintenance) - 9 January to 10 March 2006 (42 S/T days, plus 3 days maintenance) - 13 March to 12 April 2006 (20 S/T days, plus 3 days maintenance) OR - 21 August to 18 September 2006 (16 S/T days, plus 3 days maintenance)


TF S1: Consolidation of ITER database and reference scenariosA. Sips (IPP, Garching); R. Buttery (UKAEA, Culham); T. Loarer (CEA, Cadarache); &D.Frigione

TF S2: ITER Advanced ScenariosX.Litaudon (CEA, Cadarache); C. Challis (UKAEA, Culham); F.Crisanti (ENEA, Frascati); & D.Moreau

TF M: MHDS.Pinches (IPP, Garching); R. Koslowski (FZJ, Jülich); & S.Arshad

TF H: HeatingJ. Ongena (ERM/KMS, Brussels); J. Mailloux (UKAEA, Culham); & D. Moreau

TF E: ExhaustR.Pitts(CRPP-EPFL,Lausanne); W.Fundamenski(UKAEA,Culham); V.Philipps(FZJ,Jülich); & B.Goncalves

TF D: Diagnostics A.Murari(RFX,Padova);J.Brzozowski(VR, Sweden);E.delaLuna(CIEMAT,Madrid);R.Pasqualotto B.Goncalves

TF T: TransportP. Mantica (ENEA, Milano); P. Strand (VR, Sweden); V. Naulin (Riso, Denmark); & H. Nordman

TF FT: Fusion TechnologyC. Grisolia (CEA, Cadarache); P. Coad (UKAEA); & G. Piazza, S.Rosanvallon

TF DT: Deuterium-Tritium Operation K-D. Zastrow (UKAEA, Culham); & M. L. Watkins

Task Force Leaders/Deputies & CSU ROs


Significant Upgrade of JET Scientific Capabilities in 2005-2006

End 2005- MkII-HD divertor (high triangularity, high power operation)- 3 dB couplers for ELM resilience on 2 of the 4 existing ICRH A2 antennas- Improved Neutral Beam neutralisers (+ 1.5 - 2 MW)- 14 (+2) new or upgraded diagnostics / systems- Disruption mitigation valve

End 2006- ITER-like ICRH antenna- External conjugate-T for ELM resilience on remaining ICRH A2 antennas - LHCD control electronic refurbishment- Smaller diagnostics


JET ICRF System 2004

A

B

C

D

1/2

1/2

1/2

4/8

1/2

Reliable Power into H/L


JET ICRF System : 2005/2006

JET-EP

2005

end 2006/begin 2007

3dB couplers

end 2006

conjugate T

A

B

C

D

3/4

6/7.2

1/2

1/2

Reliable Power into H/L

2005 : 5/8end 2006/2007 : 11/15.2


• Introduction of septum to improve neutralization

• Further increase power output per source (+0.3MW)

<1.4MWNo Septum

1.7MWWith Septum

BEAM

More NB power with Septum NeutraliserMore NB power with Septum Neutraliser

All 8 PINIS of Oct 8 and PINI1 of Oct 4 will be equipped with the septum neutralizer in 2005


Phase Octant 8 Octant 4 RemarksEnd 2003 8 × 1.4 = 11.2MW 11. 5MW • Neutralisati ondeficit

• M ax voltage limi ted to120k V unt il Decel(electron suppressi )ongri d Powe r Supp ly isuprated. Concer ns overIon Sourc e Backplate

2005 8 × 1.65 = 13.2MW 12MW • Expecte d benefi tofimprov edneutralisers

• Upgr ade t o Dece l PS(2.8kV → >3.5kV)

• 125k V max.voltageassumed

• 2 Oct 4 ant 80kV PINIsre-gapp ed to increasecur rent55A→60A

NBI - Forecast for 2005 NBI - Forecast for 2005 NBI power to Torus

==> NBI Power in 2005 :==> NBI Power in 2005 :25MW max (~30-50% rel.), 23.5MW(~60-70% rel.) 20.5MW (90% rel.)25MW max (~30-50% rel.), 23.5MW(~60-70% rel.) 20.5MW (90% rel.)

all PINIs 1 PINI out 3 PINIs out all PINIs 1 PINI out 3 PINIs out


• With 24 klystrons available :

• Reach 5MW/5s and 4MW/15s on L-mode plasma.

• so that 3.0MW/15s is available reliably for Task Force experiments (with good coupling).

• From ~ end november 2005 only 21 klystrons will be available (in view of future refurbishment) : only 2.5MW/15s will be available.

• Special restart tasks to improve LH operation:• Specific tests to assess consequences of grill damage.

• High power commissioning of launcher on H-mode plasma (as opposed to L-mode only).

• Radiation protection needs to be re-commissioned following commissioning of new bolometer camera.

LHCD - 2005 Power Forecast


• Handle up to 40MW power for 10s with strike point sweeping• More flexibility for ITER matched triangularity plasmas (U~0.44, L~0.56) at higher Ip

(3.5-4MA)• Refurbishment of divertor diagnostics• Operation in 2005

Power handling with ITER-like plasma shapes: modified divertor (MkII-HD) installed

ITER shape High Plasma

High Field Side Gap Closure tiles: protect divertor diagnostic cables

Load Bearing Septum Replacement tiles: Increased power handling


• Objective : measure Te and ne at high resolution (ITB plasmas, plasma edge)• Main Characteristics : • 60 points for R=3.0-3.9m• 1.5cm resolution• 20 Hz repetition rate• predicted accuracy of 15% at ne=1.0x1019m-3

High Resolution Thomson Scattering


Core Charge Exchange Recombination Spectroscopy

• Objective : full radial profile of impurity density, Ti and toroidal rotation

• Main Characteristics : • Time resolution : from 5 to 10ms• Radial resolution : ~ 6cm (40 points in R=2.7-3.7m)


Halo Current Sensors

• Objective : measurement of value, current density, toroidal and poloidal distribution and nature of Halo Currents (asymmetries, filaments, correlation with kink instabilities,...)• 4 sets of probe arrays at interoctant positions Oct 1-2, 3-4, 5-6, 7-8

• Main Characteristics : • 5kHz analog bandwidth• 12dB S/N ratio


Wide View Infrared camera

• Objective : temperature distribution of first wall (ELMs, disruptions), survery of ICRH antenna

• Main Characteristics : • Full poloidal cross-section, centred on ICRH antenna• 5-10ms time resolution• 10-20mm spatial resolution


Content of Talk

• JET Operations End 2005/Early 2006

JET Operational ScheduleExperimental Planning for Task Force HeatingJET Upgrades available End 2005/Early 2006

• JET Upgrades planned for End 2006

High Power Prototype ITER like antenna

• Long Term Plans for JET

Beryllium WallMore Heating PowerImproved Pellet Capability


Main aim of Task Force H in 2005-2006

• Make progress in issues specifically for ITER– Study of coupling of LH/ICRH under ITER relevant

conditions and scenarios

– Understanding off-axis NBI current drive

• Optimise Heating/Current Drive scheme (including coupling) for use by other Task Forces : Mode conversion, Fast wave coupling schemes, Minimize interaction of LH and ICRH at JET,...

• Physics topics : rotation studies with ICRH, Fast particle studies

• Maximise LH and ICRH coupled power at JET (including: understand reasons for operational limits and explore solutions to push these limits)


ICRH coupling to ELMy plasma improved with conjugate-T matching scheme

Conjugate T matching

Low Power (200kW) Tests Succesfull - dec 2003; High Power with ICRH High Power Prototype (7.2MW design) - end 2006/2007


• ELM resilient Conjugate-T antenna with Internal Matching• High Power Density• ~7MW additional power

~40kV

Antenna straps

Capacitors ~5-6 kV

Challenging Project:• Voltage Stand-Off in Capacitors• (High) Precision C tuning for Matching• Forces during disruptions

ELM Resilient ITER-like ICRH antenna under construction (operation end 2006/2007)

R.Goulding, ORNL

Antenna Prototype tests

Key demonstration in preparation of ITER

antennas


Content of Talk

• JET Operations End 2005/Early 2006

JET Operational ScheduleExperimental Planning for Task Force HeatingJET Upgrades available End 2005/Early 2006

• JET Upgrades planned for End 2006

High Power Prototype ITER like antenna

• Long Term Plans for JET

Beryllium WallMore Heating PowerImproved Pellet Capability


Until ITER starts: JET still has significant technical capabilities which can be used to

prepare for ITER operationOn short-term (2005/2006), JET’s scientific capabilities are being extended, with construction of:“ ITER-like ” antenna and new plasma diagnostics

JET’s key components (vacuum vessel, magnets) havenot been used for more than 15% of their fatigue lifetime,although regular maintenance is needed on auxiliaries

On longer term (2007-2010), JET can be used: • to develop further operating scenarios in

conditions closest to those of ITER;• to optimise more ITER auxiliaries

Requires “ITER-like” wall conditions andincreased heating power


Planned “ITER-like” wall experiment on JETOnly JET can prepare ITER operation with the relevant materials combination

Preparation of ITER plasma operation in world-wide unique conditions

Decide as late as possible (2007)


• Material erosion and migration with relevant mix of materials

• Tritium inventory control

• Wall lifetime

• Study of damage due to transients (ELMs and disruptions) e.g. melt layer loss studies

• control / mitigation techniques Limit disruption / ELM damage

• Reference Option (all-W divertor): Operate without C - radiation

• Option with C targets: Test de-tritiation techniques

An essential stepping stone to ITER

Demonstrate routine / safe operation of fully integrated ITER compatible scenarios at 3-5MA

power upgrade (40-45 MW overall power) to operate at high performance and high densities

ITER like wall project for JET Key Objectives


1MJ ELMs in JET wall loading 10 – 40 MJm-2s-1/2 divertor Be-melting (~ 16 MJm-2s-1/2) divertor C-ablation (~ 35 MJm-2s-1/2)

ELM melt damage - Be target

1-2MJ ELMs required to study melt layer effects on W target

achievable with 10-20MJ stored energy

ELM effects on the W ( or C) divertor in JET


Planned Upgraded Pellet Injection :High Frequency Pellet Injector Project (PELIN,

St.Petersburg)

>98%

33 ± 20 mm3

17 ± 20 mm3

300 - 500 m/s

(LFS)

16 Hz

unlimited

D2

Required for ELM control

>98%

35 - 65 mm3 adjustable

150-600 m/s adjustable

(HFS)

1 - 15 Hz adjustable

unlimited

D2, impurities

(+DT/T2 later?)

Required for deep fuelling

92 ± 20 mm3

50 ± 20 mm31 - 2 mm3 adjustablePellet size

300 - 500 m/s

(HFS)

50-200 m/s adjustable

(LFS)

Pellet speed at injector exit

16 Hz10-60 Hz adjustableMaximum frequency

>98%>98%Reliability

unlimitedunlimitedNumber of pellets / pulse

D2, DT, T2, impurities

D2Fuel

Required for deep fuelling

Required for ELM control

JET ITERObjective: ELM control & deep fuelling

JET needs are close to ITER needsEncouraging results obtained on TS (10 Hz) and on JT60-U (50 Hz)

with a screw extruder system


0 10 20 30 40MW

40s

30s

20s

10s

0

Planned increase of Neutral Beam Power

Changing the magnetic structure of the ion sources from present supercusp to pure chequerboard configuration and modifying the PINI accelerator:

- Increase of the extracted molecular ion fractions (D2+, D3

+) higher

neutralisation efficiency higher E/2 and E/3 neutral beam fractions.

- Increase of the ion source plasma uniformity lower average beam divergence better beam optics higher transmission;

- Increase of the extraction apertures diameter and reduction of the accelerator gap beam current increase (60A65A).

2005


More power will bring JET plasmas even closer to ITER

Example: ITER ELMy H-Mode data base

* and * normalised to ITER

*, * range / other large tokamaks

RECENT JET RESULTS

FUTURE :

2006/2007 JET Operation

High N 4.5-5 MA 40 MW closer to ITER


40-45 MW heating power will allow highly ITER relevant studies of plasma regimese.g. High density bootstrap-dominated advanced regime in steady regimes

p~1.0MW

p~5MW

simultaneous increase of

Iboot/IP and nT

high nedge for metallic wall

compatibility

Full lines: n ~ nGW

at q95 ~5 and N up to 3(ITER Relevant domain)

Dotted lines: n < nGW

2003-2004

2005-2006

2009-2010

Need more power at JET for AT scenarios


Conclusion Proposed JET Programme in Support of ITER

2005-2007Strong focus on preparing ITER detailed design and ITER exploitation, including the commissioning and initial operation of an ITER-like ICRH antenna and preparation

for proposed changes of wall/divertor materials and increased heating power Installation & exploitation of JET-EP enhancements, including diagnostics

2008 ShutdownInstallation of major new capabilities

“ITER-like” wall NB power upgrade High frequency pellet injector Diagnostics Other small enhancements (tbd)

EFDA Steering Committee approved first three Experimentation in 2009-2010


Appendix 1 : Summary of design characteristics of new diagnostics at JET

• The next pages contain a concise summary of the design charactaristics of the various new diagnostics in JET. Latest information on their actual implementation on JET and on the date of availability can be found on the Task Force D website in JET:http://users.jet.efda.org/pages/d-task-force/index.html, under topic : latest on 2005 JET enhancements


Location vertical camera KB5V on MVP octant 3 (replaces KB1).Horizontal camera KB5H on MHP octant 6

Physics outputs Total radiation power, radiation profiles through tomographic reconstruction

Lines of sight KB5V 16 channels cover all cross section (13-25 cm separation at midplane);

+ 8 channels dedicated to divertor(8 cm separation at top of divertor).

KB5H 4 upper channels (vertical separation ~ 15 cm at R=3m);

+ 12 middle channels (separation 18-22 cm);+ 8 lower channels for divertor (separation ~ 8 cm)

Timing Temporal resolution 2 msSampling frequency 10 kHz for 50 s.Real Time: from 1 kHz for 80 s to 5 kHz for 16 s

Accuracy Equivalent noise 1 μW/cm2 at gai n = 5000

PPF B : OLO line integra ted powers, tota l radi atedpow .erBURA (radiation profiles from Abel inversio ),n BARA (radiatedpower on targets, emissivity from tomography), BOLT(tomograph ic reconstructions) availabl e late r a s priv atePP ’F s

Comments Better accuracy and time resolution than the old KB1, whichhad time resolution 20 ms and equivalent noise 60-70 μW/cm2.K 5B and KB3 (divertor bolometer) diagnostics together enhancethe tomograp hy capabilitie s in thediverto r region.

KB5 - Bolometer cameras


Physics outputs Total radiation power in the divertor region, radiation profiles through tomographic reconstruction

Task of Project refurbish damaged channels, open blocked views, optimise view for new divertor and KB5(does not cover outer divertor): good coverage of all X points and strike points

- Replacement of the inner-ring remote handling camera (KB3 camera 5) by new camera withoptimised view and technical improvements;

- Replacement of outer-ring remote handling cameras (KB3 cameras 3 and 4) by new cameraswith optimised view and technical improvements. Modification of protection tile to open the view for camera 2

Lines of sight 8 +4 channels cover the divertor cross section (8-9 cm separation at midplane of divertor)

Timing Temporal resolution 2 ms. Sampling frequency 4 kHz for 125 s

Accuracy Equivalent noise 1 μW/cm2 at gai n = 5000.

PPF B3D4 and B3 4E : line integrated power ,s BARA (radiated power on targets, emissivity fromtomography), BOLT (tomographic reconstructions) available later as private PPF (thesereconstructi on ar e availab leon ly i n combinatio n wi thK 5B H/ V measurement )s .

Comments Better accuracy than the old KB3, which had equivalent noise about 50 μW/cm2. Because theouter divertor region is not recovered by KB5H, the divertor tomography is only possible incombination of K 5B and new KB3 camera .s

KB3 Bolometer cameras in divertor


Physics output Edge radial profiles of ion temperature Ti (oct.4), poloidal plasma rotation velocity, vθ

(oc .4 t & 8), toroida l plasma rotation velocity vϕ (oc .4)t andimpurit y io n density.

Spat ial info Profile s with:

-ks7 :a 8 points, up-dow n symmetr ic view, i n R = 3.6 4 – 3.76 m (oc .t 4), 2.5 cm resolution

-ks7 :b 5 points -up dow n symmetr ic view, inR = 3.7 8 – 3.84 (oc .4)t , 2.5 cm resolution.

- 7ks c: 6 point s core vθ profile s wi 6th point s i n R = 3.2 8 – 3.84 (oc .8)t , 5 - 10 c m resolution

Li ne o f sight alon g PIN I 4 an d 6 ofoc 4tant NB I an d PIN 4 I an 6 d of oc tant8 NBI

Timing tim e resolution set to accommoda tespecifie d accuracy, minimu m 10 ms

Accuracy bett er th an 10% fo r Ti (oc .4)t and5 km/se c fo r vpol (oc .8)t .

PPF ne w version s o f CX SE to accommod ate new lay .out

Comments New periscopes, fibres, CCD cameras, spectrometer to restore u -p down symmetric view inoc .t 4 and to move core view from octant 4 upper port(15 l. .o s.) to octant 8 lower port (nobackgroun d li ght fr om diverto r allo ws coverage to magnet ic a )xis . N o edg e Ti rea l ti .me

KS7 - edge CXRS

Oct 4Oct 8old


Oct. 8

Oct. 7periscope Pini 6Pini 7

Oct. 1 periscope

Physics output Full radial profile of ion temperature Ti, toroidal plasma rotation vtor and density of impurity ions

Spatial info profiles with 40 points in R = 2.7-3.7, ~6 cm resolution.

Line of sight along PINI 6 and 7 of octant 8 NBI

Timing Holospec setup: minimum time resolution 5-10ms but can be used at longer integration time.Czerny-Turner setup: minimum time resolution: 5-10ms but can be used at longer integration timeas trade-off with signal level.

Accuracy Increased sensitivity wi th new octant 7 pe riscope and new fibres connection (up to 50%improvement)

PPF: old suite of PPF’s extended to cover 5 instruments.

Comments New periscope, additional fibres, six faster CCD cameras, two spectrometers (Holospec). Numberof spatial measurements improved by 2, temporal resolution by 5-10. Some dedicated linesof sight looking at pa ssive emission. Enhanced sensitivity of the entire system (optics,spectrometers and CCDs) increases the accuracy and reduces the detection limit. Now Observable species: C, He, Ne, Be, N, O, Ar, Beam emission.

KS5 - Charge Exchange Recombination Spectroscopy

old


Physics output Temperature distribution of first wall

Spatial info 70° field of view covers full poloidal crosssection, centred on ICRH antenna in octant 2,spatial resolution 10- 20 mm

Timing time resolution 10 msec full frame, d own to100 μsec wi thsmallest window (128 8x pixels);acquisitio n max 10 sec

Accuracy temperature could be calculated with ≤ 10%accura cy i n th e ran ge 160-2000 °C

PPF n o PPF: ph otonfl ux i n LP F produce d intershottemperature calculation is not part of theproject

D T comp .at no

Comments availabl e on ly fro m Sept. 2005 onwards;ITER like optical design with wide field of view;visible channel available for future exploitati .onN o zoom

KL5 - Wide angle Infrared View (IRV)


0.01

0.1

1

10

100

1000

5 10 15 20 25 30 35

JET Lost Alpha Faraday Cup Signalsr=46 mm (front when tiles 5 mm behind poloidal limiter)

A=961 mm2; D:T=1:1; shadowing included

Signal (nA)

Poloidal position (degrees)

1 MA, 1 T, =5.07

2 , 2 , MA T=3.62

3 , 2.9 , MA T=4.8

3.8 , 3.8 , MA T=3.7

4.5 , 3.5 , MA T=3.1

Nominal noise level

Optimistic noise level

PoloidalLimiterFaradaycups

KA2 Lost alpha diagnostics (LAP): Faraday Cups

Physics output: Poloidal profile of fast ion loss with crude energy resolution and radial profile.

Timing time resolution 1 ms (sampling rate)

Accuracy current noise level in range 0.2 – 5 nA; dynamic range: 1 nA/cm2 – 100 μA/cm2; energy resolution for 3.5 MeV -particles ~ 15-50 % (energy is resolved in 2 to 7 channels);detectabl e range of-particle s energies 1-5about MeV

PPF Tota l lo ss curren t to ea ch c up (10 places)me an energ y o f los t ion (s 10 places);me an poloida l angle of loss;radia l scrap e offlen gth o f ion s (2 place )s ;estim atedgloba l lo ss fracti on (i f D )T .All of the mar e produc edautomatica llyfro m C15

Comments measures losse s : of- DD char ged fusio n product (s 1 Me V Tritons, 3 Me V proton , s 800 ke V 3H e ion )s ;- D T -particle (s 3.5 MeV)- I CH ta il ions- -particle s fr om4H e injectionAs a functi on ofpoloida l positio , n energ y an d pitc h angl e o f the particl .e


KA3 - Lost alpha diagnostics (LAP): Scintillator probe

Location Octant 4, scintillator probe in lower limiter guide tube

Physics output Energy and pitch angle distribution of lost fast ion:

- dynamic range measured current density: 10 pA/cm2 – 1 μA/cm2; detecti on limi :t 2.4 x 104 s-1 -particles;

- dynam ic ran geenergy: gyrorad ius = 20-140 mmwith 15% accur acy( ~77 m m fo 3.5r Me V -particle s a tBT = 3.5 );T

- dynam ic ran gepitc h angle 30° - 86° wi th5% resolution.

Timing tim e resolutio n 0.1 ms (photomultiplier )s

PPF Tota l lo ss curren t (eve rypulse);scintillato r imag e (2 D im age o n CC D a nd fast 4er 4 x photomultiplie rs array);me an energ y o f los t ion (s fro mbot h CC D a nd photomultiplier s array);me an pitch angl e o f los t ions;(las t th reePP Fs on lyo n demand)

Comments measures losse s :of- DD char ged fusi on product (s 1 Me V Triton , s 3 Me V protons, 800 ke V 3H e ion )s ;- D T -particle (s 3.5 MeV);- I CH ta il ion ;sCritica l issues: vignetti ng fr omTA E antenna’s an d heatlo ad fr omNBI


KM9 - Magnetic proton recoil spectrometer (MPRu)

Physicsoutput

neutron spectrum in the range 1.5-20 MeV (either DD or DT neutrons) and from it:

- different velocity components of fuel ion population (temperatures and amplitudes);- absolute fusion power and its thermal and supra-thermal reaction contributions (either D or DT);- fuel ion toroidal rotation;- plasma response to NB and RF heating;- info on fast fusion product ions (from -particl e knock-on for DT or fr omtri tonburn- up fo r D).

Li ne o f sight semi-tangentia l vie w (47°), elevation 4.85°

Timing tim e resolutio n vari es dependi ng o n count ratea ndcomplexit y of spectru ; mtypically, dow n to10 m s fo r DT an d 1 s fo r D

Accuracy S/N improved about 1000 x t o anexpected 10^ 6 o r bette r fo r 14-Me V neutrons;S/N > 1000 x improve d fro m ol d ≈1/10 fo r 2.5 -Me V neutrons;energ y resolution variabl ; e typicall , y to be s et at6 % an 2.d 5 % (FWHM) Dan d DT, respectively.

PPF neutron flu x (rel atedt o yiel d ra ),te pea k energ y a nd energ y shif t of peak, i on (effective) tempera ,ture toroida l rotati ,on 32-poi nt histogram relate d to neutro n spectrum

Comments - upgrade d versio n of existin g M PR (MPR )u measure s als o DD neutrons;- the diagnostic is calibr ated t o affor d absolu te measure mento f neut ronener gy and flux; increased accura ;cy- new double-layer scintillator and waveform recording system provide high immunity to background to allow

detecti on of mos t neutro n emissio n component s t o thelimi t s et b y counti ngstatistics;- ne w contro & l monitorin g system forsetti ng to calibrate d workin g point s a ndstabilit y checks;


KM11 - Time of flight for optimised rate (TOFOR)

Physics output neutron spectrum in the range 1-5 MeV (DD neutrons) giving:

- velocity components of deuteron population (temperatures and amplitudes);- thermal and supra-thermal reaction contribution to the fusion power.- plasma response to NB and RF heating

Line of sight vertical through plasma centre recording neutrons emitted perpendicular to magnetic axis

Timing time resolution varies depending on spectral complexity and count rate; typically, from 30 ms at 300 kHz for a neutron yield rate of 5·1016 n/s

Accuracy S/N > 100 at maximum count rate (higher for lower rates);

energy resolution ≈5 % (fixed, FWHM) corresponding to thermal Doppler broadening at Ti=2.2 keV

PPF measured TOF spectrum, centre and width of neutron peak

Comments In replacement of a m othballed time-of-flight (TOF) spectrometer, a new TOF spectrometer foroptimised rate (TOFOR) is to be installed for neutron emission spectroscopy. It has:

- 100x higher neutron count rate than the first generation TOF spectrometer (KM3);- new control & monitoring (C&M) system for setting to calibrated working points stability

checking;- improved (C&M supported) calibration accuracy compared to TOF;- complementary measurements to be made with MPRu at 47o to magnetic axis.


MOD 2

MOD 3

MOD 4

MOD 5

MOD 6

MOD 7MOD 8

MOD 9

MOD 10

MOD 11

MOD 12

MOD 13

MOD 14

MOD 15

MOD 16

MOD 17

MOD 18

MOD 19MOD 20

MOD 21

MOD 22

MOD 23

MOD 24

MOD 1

OCTANT 7

OCTANT 8

OCTANT 1

OCTANT 2

OCTANT 3

OCTANT 4

OCTANT 5

OCTANT 6

PROPOSED NEW POLOIDAL PICK-UP COILS

PROPOSED NEW POLOIDAL PICK-UP COILS

PROPOSED DIVERTOR COILS

PROPOSED NEW TOP PROBE ARRAY

PROPOSED NEW TOP PROBE ARRAY

Location external coils: Limb probes for radial distribution of vertical stray field (3 f lux loops, 3 pick-up coils, 3 H all sensors ); Collarprobes for vert. + radial field (1 pick-up coil + 1 Hall );

internal coils: 3 subsystems of two field components pick-up coils: Upper coils (5 pairs), Outer poloidal Limiter Coils (7 fa sttangential + 7 slow normal) and Divertor Coils (7 pairs) replicated in 2 octants

Physics output - improved general accuracy of equilibrium reconstruction and MHD analysis;- provided ability to reconstruct upper X-point;- improved response of vertical stabilisation system for highly elongated plasmas, including n=2 compensation;- diagnosed iron saturation with external sensors

Timing bandwidth up to 50 kHz; MHD coils up to 1 MHz. Hall probes 100 Hz sampling rate

Accuracy calibration with 0.5 % accuracy. Hall probes sensitivity 0.1 mT

PPF - MAGN / MAGO updated to include calibrated and TF compensated new sensors;- new analysis tool to compare data with predictions for commissioning and data validation;- new XLOC to include new sensors, with flexibility to change coil set with approved configurations;- implementation of new XLOC in PPCC, XSC and WALLS for plasma control;- new magneto dynamic model (up to 1 kHz) and dynamic XLOC for plasma shape reconstructions during sweep and ELMs;- calibration of fast coils for MHD with transmission lines across full bandwidth

Comments vertical stability controlled only by 2 poloidal sets: disruption risk from n=2 in high current remains; inner wall coils cancelled:vertical stability unlikely to improve; external sensors: absolute measurements only with Hall probes; feed through shared withTAE power lines might induce noise; EFIT will be upgraded to include the new coils, with transition period to optimise (Operatortask).

KC1 - Magnetics


KC1H - Halo current sensors

Location - 8 Rogowski coils behind upper dump plate ;- 2 BT pick up probes at the edges of the dump plate;- 4 sets of probes arrays at the inter octants 1-2, 3-4, 5-6, 7-8

Physics output Halo current flowing through plasma and vacuum vessel during plasma verticaldisplacement events;

IH density distribution, localisation and rotation; toroidal and poloidal IH asymmetries

Timing sampling rate up to 10 kS/s throughout all JET pulse; 5 kHz analog bandwidth

Accuracy Rogowski coil: global coefficient K = 1.8 10-7 Vs/A (signal of about 30 mV for typicaldisruption) and expected pick-up 6-7 mV give S/N ~ 12 dB

PPFHalo currents (8 probes), toroidal field (inner and outer probes);- integrated BT and IH corrected for offset, drift, effective area, pick up;- Toroidal and poloidal peaking factors; mean and total IH, toroidal position max IH,


KC1T - Toroidal Alfven Eigenmodes antennas (TAE)

Location two groups of 4 antennas ( one active, the o ther passive), symmetrically located in thetoroidal direction (octant 4 and 8), close to the plasma (6 cm). Detection with passive antenna, fast magnetic sensors and reflectometry (KC1N)

Physicsoutput

- Determination of stability characteristics of fast particle driven Alfven modes (n=3-15);- info on -particl e pressur , e D/T densit y ratio

Timing - tim e resolutio n ~ 50 ms (possibl e rea l time mode tracking, require s modificati ono f AELM);- fu ll pul se (12 s) coverage

PPF Directly:- tracking of stable mode: frequency (+/- 1 %), damping rate (+/- 10%), amplitude and

antenna-plasma coupli ;ng- spatial structure of TAE (post-shot analysis): errors depend on internal fluctuation

diagnost ics PP F availab le on request.

Derive d quantities:- plasm a rotation;- fast particl e content/distributio , n isotop e composition (erro r depend s o n plasm a scenari ).o

Comments previously used saddle coils allowed excitation of only low toroidal mode numbers (n=0,1,2 ),stabilit y o f hi gh n mod es impor tantf or ITER


Microwave access (MWA)

Physicsoutput

Replace lossy waveguides (60 dB attenuation) with 3 new low attenuation corrugated waveguides and acluster of 6 optimised antennas for Reflectometry (4 antennas and co rrugated wg) and oblique ECEdiagnostic (2 antennas and smooth wg).Oblique ECE tests the departure from a Maxwellian distribution of the bulk electrons by looking at the ECEat φ = 10° an d 20° to the norma l t o themagnet ic fiel .d

Transmission Corrugate d waveguid es h avea n estimate d attenuation of 30 d B compared to 60 d B o f t he ol d ones

Frequency K 8G a: acquisitio n frequen 0cy .1 - 100 M Hz with typically 50-1 00 point / s profile (e. . 50g point s profile s ar e measure d eve ry50 μse c a t1 M )Hz

PPF improv edS/ N will:

- improve performanc e o f existin g fou r K 8G b correlatio n reflectometers (76, 85 , 92, 103 GHz) whichha vebeen routin elyoper atedproducin g JP Fs, b utsufferi ng fr omlo w S/N; n o P PF fores een fo r K 8 ;G b

- allow reinstatement of the KG8a wideband reflectometer ( 50-75 GHz) for density profilemeasurement s a t thee dge(PPF wit h densit y profil e will beproduc ed fr omC15).

Comments Attenuati ,on return loss, cross-talk, polarisation rotation and cro -ss polar effects will be measured over 60-190 G Hz for corrugate d waveguides, ove r 70-400 G Hz fo r smoo th on es forECE


Physics output Broadband calibrated ECE electron temperature measurements.The oblique ECE tests the departure from a Maxwellian distribution of the bulkelectrons by looking at the ECE at φ = 10° an d 20° to the norma l t o themagnet ic fiel .d

Technicalcharacteristics

Tim e resolution (t o obtai n a single inter .):f 9 ms

Spectr al rang : 70e -800 GHz

Spectr al resoluti : 8.on 5 G Hz (correspondi ngt 14 o cm)

PPF JP F exist s with raw interferograms. PPF with calibrated spectra and Te profiles, similar toKK1, is und er development

Comments The K 5K Michelson ECE FTS, will update the JE T diagnostics capability in the keyarea of ECE and electron temperature measurement, replacing the aging KK1 systemwith a modern state-of-the-art instrume .nt This refurbishment will give an improvementboth to the spectral (factor 2, down to 6 GHz) and temporal (factor 3, up to 5 ms)resolutions.

KK5 - Michelson Electron Cyclotron Emission Oblique ECE


Physics output New 92 channels isolated digitiser PCI boards p rovide fast acquisition channels to anumber of systems (it complements existing fast acquisition systems like CATS andKK3F)

Allocation - KC1M: 32 ch for old (23) and new (14) fast magnetic coils (fixed allocation).- KC1N: 32 ch for KK3, KG3, KG8b, KC1T, KG1 (variable allocation through

distribution panel);- KK5: 8 ch;- NBI: 16 ch for ELM coupling development

PPF KC1M: JPFs and LPFs produced, not PPFs: 4 magnetic signals to JPF, rest to LPF.

Typical time window: 8 s @ 2 MHz; max window @ 2 MHz: 16 s for JPF, 32 s for LPF

Comments KC1M now replaces KC1F, which is scrapped. The role of CATS is under discussion(could be reduced 30%). Large quantity of extra data (up to 8 GB) requires sensibledemand by users (read only time window of interest) and efficient data collection andanalysis procedures. System partially commissioned during C14

Fast ADC’s (incl. KC1M, KC1N)


Physics output Several techniques to address the problems of Tritium retention in divertor and mainchamber and erosion/deposition on metallic mirrors

Techniques - 4 new QMB’s + replacement of existing QMB with time resolution of one JET pulse;- 1 new QMB dedicated to Beryllium deposition;- 5 rotating collectors with resolution of either 25 or 50 JET pulses and coverage of

3000 pulses;- deposition monitors;- full poloidal set of 7 smart tiles in divertor and other smart tiles at a minimum of 10

poloidal positions in the main chamber;- mirror test units ( Stainless Steel and Molybdenum) in the divertor (3 poloidal

positions) and at outer mid-plane

PPF only for QMB: frequency difference between exposed and shielded crystals will beconverted to a deposition rate, based on laboratory calibration of film thickness

Comments two of the new QMBs can be heated to 300°C; a shutter to each QMB allows for part of each pulse to be selected

Tritium retention studies (incl. KV6 - QMBs)


Appendix 2 : Details of Task Force H sessions in 2005/2006

• The next pages contain a concise summary of the sessions planned/merged or postponed for Task Force H. More information can be found on the Task Force H webpage at JET.


Experiments planned for High Level Commissioning Campaign

Proposal . Status Author Nr. Sessions

Maximise LHCD power in plamsas with ELMs Acc. K.Kirov 2

Maximisation of ICRF power on ELMs (including work for 3 dB couplers)

Acc. M.Mayoral 2

Improved LH wave coupling during operation with ICRH antenna A and B

Acc. K.Kirov 2

ICRF antenna array S-Matrix measurements under plasma loading P-B. I.Monakhov 0


Topics in Task Force H --- LHCD

Optimisation of LHCD operation (Headline 1 and 2)

Proposal Status Author Nr. Sesssion

s

Coupling of LH waves in the hybrid scenario at high triangularity Merged A. Ekedahl

2

(2)

Coupling of high power LH waves in ITB plasmas at high triangularity Merged A. Ekedahl

Optimise LH coupling in plasmas at high triangularity with ELMs using gas puffing

Merged J. Mailloux

LHCD coupling, especially in ITER-like conditions and including effect of triangularity on SOL ne (Headline 2 and 3)

Proposal Status Author Nr. Sessions

Maximise LHCD power in plasma with ELMs Acc. K.Kirov 2 HLC

(2 HLC)Improved LH wave coupling during operation with ICRH antenna A and B (with 3db couplers).

Acc. K.Kirov


Topics in Task Force --- LHCD ITER relevant coupling of LH waves (Headline 2 and 3)

Proposal Status Author Nr.Sessions

Characterisation of SOL during LHCD and gas puffing Merged K.Rantamäki

3 (2)

Characterisation of LH coupling and parasitic absorption in L-mode plasmas

Merged A. Ekedahl

Bright spots generated parasitically by lower hybrid power Merged K. Rantamäki

Non-linear Edge Effects at LH Wave Launching Merged V.Petrzilka

Observation of Energetic Particles Generated in Front of the JET LH Grill

Merged V. PetrzilkaLH wave physics: current drive, synergy with ICRH in mode conversion regime, parasitic absorption on fast ions, startup (Headline 2 and 3)Proposal Status Author Session

s

Fast ion absorption of LH waves Postp. L-G.Eriksson 0 (0)

Current Drive Profile Control with LHCD Phasing Acc. Yu. Baranov 1 (1)

Lower Hybrid Current Drive Assisted by ICRF Mode Converted Waves

Postp. Yu. Baranov 0 (0)

Lower Hybrid Counter Current Drive Postp. M. Goniche 0 (0)

Plasma Startup in JET using Lower Hybrid Wave without induction Postp. M.Peng 0 (0)


Topics in Task Force H --- NBI

NBI physics : fast particle physics, on/off axis current drive and poloidal momentum generation (Headline 2 and 4)

Proposal Status Author Sessions

Investigation of fast ion dynamics due to on-axis and off-axis NBI Acc. I.Jenkins 2 (2)

Study of poloidal momentum input by NBI and control of the ExB shearing rate

P-B K.Crombe/

Y.Andrew

0 (0)


Topics in Task Force H --- ICRH Optimisation of ICRH operation, especially in ITER-like conditions (far distance and large ELMs) (Headline 1,2 and 3)


Maximisation of ICRF power on ELMs Acc. M.Mayoral 2 (2) / HLC

ICRF coupling with gas injection in ITER like configuration Acc. M.Mayoral 1 (1)

Peculiarities of ICRF antenna loading during ELMs P-B I.Monakhov

0 (0)

ICRF antenna arry S-matrix measurements under plasma loading P-B I.Monakhov

0 (0) / HLC

Mode conversion (Headline 4)Proposal Status Author Sessions

Development of reliable ICRH mode conversion in the hybrid scenario and application of this tool for transport studies

Merged D.Van Eester 1H,1T

(0) Mode conversion in ITB plasmas : electron transport study Merged D.Van Eester

Fast wave studies (Headline 2 and 4)Proposal Status Author Sessions

Fast Wave Current Drive Heating in ITB Plasmas Postp. T.Hellsten

0 0Investigation of RF-sheath effects and parasitic absorption during ICRH

Postp. T.Hellsten


Topics in Task Force H ---- ICRH

Plasma rotation with low or no external momentum (Headline 4)Proposal Status Author Sessions

The influence of magnetic field ripple on toroidal rotation in plasmas with little or no external momentum injection

Postp. L-G.Eriksson 0 (0)

Plasma rotation with low or no external momentum source Merged L-G.Eriksson/T.Hellsten

2 (2)

Feedback control of sawteeth (Headline 4)Proposal Status Author Sessions

Feedback Control of the sawtooth period by using the extreme shape controller to vary the location of the RF resonance relative to the q=1 surface during ICCD

Merged

F.Sartori

2 (0)Feedback Control of the sawtooth period by using a variable ICRF frequency or the extreme shape controller to vary the location of the RF resonance relative to the q=1 surface during ICCD

Merged

M.Lennholm

Ion Cyclotron Current Drive control of sawteeth generated by simulated alpha particles

Merged

M.Mayoral


Topics in Task Force H --- ICRH

Fast ions, ITER relevant schemes and transport studies (Headline 4)


Exotic neutron production reactions in ICRF minority heated plasmas

Acc. M.Santala 0.5 (0)

Experimental study of the mechanism of fundamental ICRF heating of the majority ions in ITER-like tokamak plasma

Acc. A.Krasilnikov/D.Van Eester

1 (0)

Fast ion transport in reversed shear plasmas Postp. R.Cesario 0 (0)

Te/Ti effects on plasma energy confinement P-B. E.Asp 0 (0)


Total sessions in 80 day campaign

15.5

Total sessions in 60 day campaign

(9)

Sessions in High Level Commissioning

6

Overall Total of Sessions

21.5 (15)

Summary : Session Attribution in Task Force H


New ICRH Antenna ‘Early’ New ICRH Antenna ‘Late’• C15: Physics Campaign C15: Physics Campaign

(20d : 21/11/05 - 16/12/05) (20d: 21/11/05 - 16/12/05)

• C16: Physics Campaign C16: Physics Campaign(45d : 9/1/06 - 10/03/06) (45d: 9/1/06 - 10/03/06)

• C17: Physics camp. + Conj.T C17: Physics Campaign(18d : 21/8/06 - 18/9/06) (23d: 13/3/06 - 12/04/06)

• C18: 50%Physics Campaign + Conj.T C18: Physics Camp. + Conj.T 50% Low Power Comm. JET-EP(20d : 25/9/06 - 10/11/06) (20d: 25/9/06 - 20/10/06)

• C19: Physics Campaign + Conj.T + C19: 50% Phys. Camp + Conj.T JET-EP 50% Low Power Comm +JET-EP (25d : 13/11/06 - 15/12/06) (20d: 30/10/06 - 15/12/06)

i.e. full power JET-EP only available in 2007

Appendix 3 : Details of Planning C15-C19 (2005-2006)


Appendix 4 : Details of NBI Upgrade (2007)

• The next pages contain some technical details on the proposed neutral beam upgrade at JET.


To increase the maximum deuterium NB power from ~25MW to ~34MW. To increase the pulse length to 20s at full power and 40s and half power. To improve the reliability and availability of the JET NB System.

AimsAimsAimsAimsThe aims of the EP2 NB Enhancement are:The aims of the EP2 NB Enhancement are:

Replacing the high voltage power supplies on Octant 4 NIB with four new 130kV/130A modules, identical to those installed during the recent Octant 8 upgrade.

Replacing inter-pulse cooled components with actively cooled components:

Duct protection (hypervapotron elements);

First stage neutralisers.

This will be achieved by:This will be achieved by:

Changing the magnetic structure of the ion sources from present supercusp to pure chequerboard configuration and modifying the PINI accelerator:

Increase of the extracted molecular ion fractions (D2+, D3

+) higher

neutralisation efficiency higher E/2 and E/3 neutral beam fractions.

Increase of the ion source plasma uniformity lower average beam divergence better beam optics higher transmission;

Increase of the extraction apertures diameter and reduction of the accelerator gap beam current increase (60A65A).


Deuterium beam energy (keV)

Neutral beam power (MW)

90 100 110 120 1300.0

0.5

1.0

1.5

2.0

2.5

130kV/58A Supercusp PINI

Total

D(E)

D(E/2)

D(E/3)


Neutral beam power (MW)

90 100 110 120 1300.0

0.5

1.0

1.5

2.0

2.5

125kV/65A Chequerboard PINITotal

D(E)

D(E/2)

D(E/3)

Increase in total neutral power per PINI of ~30% Beam power fractions: Full energy component reduced by ~7%.

Fractional energy components increased ~3 times.

Implications for post-2008 JET Programme (1)Implications for post-2008 JET Programme (1)



Fuelling (1020 s-1)

90 100 110 120 1300.0

0.5

1.0

1.5

2.0


Total

D(E)

D(E/2)D(E/3)


Fuelling (1020 s-1)

90 100 110 120 1300.0

0.5

1.0

1.5

2.0

125kV/65A Chequerboard PINI

Total

D(E)

D(E/2)

D(E/3)

Increase in fuelling (single PINI) of ~70%.

Increase in fuelling per unit of injected power (single PINI) of ~30% .


Fuelling (1020 s-1/MW)

90 100 110 120 1300.0

0.2

0.4

0.6

0.8

1.0

125kV/65A Chequerboard PINI


Implications for post-2008 JET Programme (2)Implications for post-2008 JET Programme (2)

status of the jet device and planning of task force h in upcoming jet campaigns

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