nick walkerecfa-desy nikef amsterdam 4.04.2003 international linear collider technical review...

Nick Walker ECFA-DESY • NIKEF • Amsterdam • 4.04.2003

International Linear ColliderTechnical Review Committee

Nick Walker (DESY)


Where is The Report?

http://www.slac.stanford.edu/xorg/ilc-trc/2002/2002/report/03rep.htm

Available online:

Printed and CD-ROM versions should be available soon (now?)

420 pages!


History of the ILC-TRC

• International Collaboration for R&D toward TeV-Scale e +e– LC asked for first ILC-TRC in June 1994

• ILC-TRC produced first report end of 1995

• 2001: ICFA requests that ILC-TRC reconvene to produce a second report (subject of this talk)


Second ILC-TRC Charge

• To assess the present technology status of the four LC designs at hand, and their potential for meeting the advertised parameters at 500 GeV c.m.

• Use common criteria, definitions, computer codes, etc., for the assessments


Second ILC-TRC Charge

• To assess the potential of each design for reaching higher energies above500 GeV c.m.

• To establish, for each design, the R&D work that remains to be done in the next few years

• To suggest future areas of collaboration


LC Status at First TRC

TESLA SBLC JLC-S JLC-C JLC-X NLC VLEPP CLIC

f [GHz] 1.3 3.0 2.8 5.7 11.4 11.4 14.0 30.0

L1033

[cm-2s-1]6 4 4 9 5 7 9 1-5

Pbeam

[MW]16.5 7.3 1.3 4.3 3.2 4.2 2.4 ~1-4

PAC

[MW]164 139 118 209 114 103 57 100

y

[10-8m]100 50 4.8 4.8 4.8 5 7.5 15

y*[nm]

64 28 3 3 3 3.2 4 7.4

1994 Ecm=500 GeV


LC Status at Second TRC

TESLA SBLC JLC-S JLC-C JLC-X/NLC VLEPP CLIC

f [GHz] 1.3 5.7 11.4 30.0

L1033

[cm-2s-1]34 14 20 21

Pbeam

[MW]11.3 5.8 6.9 4.9

PAC

[MW]140 233 195 175

y

[10-8m]3 4 4 1

y*[nm]

5 4 3 1.2

2003 Ecm=500 GeV


OrganisationChair

Greg Loew (SLAC)

Reinhard Brinkmann (DESY) Kaoru Yokoya (KEK) Tor Raubenheimer (SLAC) Gilbert Guignard (CERN)

Steering Committee

WG ITechnology, RF Power, and

Energy Performance Assessment

WG IILuminosity Performance

Assessment


OrganisationChair

Greg Loew (SLAC)

Steering Committee

WG ITechnology, RF Power, and

Energy Performance Assessment

WG IILuminosity Performance

Assessment

WG IIIReliability, Availability and

Operability


Technology Working Group

• Injector, DR, and BDS• Power Sources

– klystrons, power supplies, modulators, low level RF etc.

• Power Distribution– RF pulse compression,

waveguides, two-beam acceleration (CLIC) etc.

• Accelerator Structures

ChairDaniel Boussard (CERN)

MembersC. Adolphsen (SLAC)H. Braun (CERN)H. Edwards (FNAL)K. Hubner (CERN)L. Lilje (DESY)P. Logatchov (BINP)R. Pasquinelli (FNAL)M. Ross (SLAC)T. Schintake (KEK)N. Toge (KEK)H. Weise (DESY)P. Wilson (SLAC)


Luminosity Working Group

• e± Sources (gun DR)• DR• Low Emittance Transport

(LET, from DR IP)– bunch compressors– main linac– beam delivery

• Machine Detector Interface

ChairGerry Dugen (Cornell)

MembersR. Assmann (CERN)W. Decking (DESY)J. Gareyte (CERN)K. Kubo (KEK)W. Kozanecki (Saclay)N. Phiney (SLAC)J. Rogers (Cornell)D. Schulte (CERN)A. Seryi (SLAC)R. Settles (MPI)P. Tenenbaum (SLAC)N. Walker (DESY)A. Wolski (LBNL)

Many new studies (simulations) performed

THIS was much more than a review!


Reliability Working Group

• Reliability– hardware components– MTBF

• Availability– fraction of time available

for delivering luminosity

• Operability– impact of (invasive)

tuning, machine studies etc.

MembersC. Adolphsen (SLAC)Y. Chin (KEK)H. Edwards (FNAL)K. Hubner (CERN)L. Lilje (DESY)M. Ross (SLAC)N. Toge (KEK)H. Weise (DESY)

R. Assmann (CERN)W. Kozanecki (Saclay)D. Schulte (CERN)A. Seryi (SLAC)P. Tenenbaum (SLAC)N. Walker (DESY)

Co-ChairsRalph Pasquinelli (FNAL)Nan Phinney (SLAC)

tech

nolo

gy

lum

inosity


2nd TRC Time-Line• Summer 2001: ICFA requests report• Autumn 2001: WGs formed • 2002 WGs meet 4 times during the year to

– define tasks– review progress– formulate summary

• October 2002: Greg Loew formally reports findings at ICFA seminar

• January 2003: Published!

Many many video/telephone conferences (Tbytes of email!)


Methodology

• Review current designs and status (achievements) of R&D, particularly the test facilities

• Identify the positive aspects of the designs

• Identify those areas of ‘concern’ and

• identify R&D that needs to be done to address these issues

• Categorise (rank) the R&D items


The Rankings for R&D

• Ranking 1

• Ranking 2

• Ranking 3

• Ranking 4



• Ranking 1

• Ranking 2

• Ranking 3

• Ranking 4

R&D needed for feasibility demonstration of the machine

what you must do before you can honestly say the machine will work (proof of principle)



• Ranking 1

• Ranking 2

• Ranking 3

• Ranking 4

R&D needed to finalize design choices and ensure reliability

Still critical R&D, but not central to proof of principle

Not mandatory before formal proposal



• Ranking 1

• Ranking 2

• Ranking 3

• Ranking 4

R&D needed before starting production of systems and components

Necessary engineering (prototyping) before (for example) transferring to industry (mass production)



• Ranking 1

• Ranking 2

• Ranking 3

• Ranking 4

R&D desirable for technical or cost optimisation

Would be useful to do but is not strictly mandatory

Basically all things that ‘fell off the list’ for R1-3


Rankings Score Sheet

TESLA JLC-C JLC-X/NLC CLIC Common

Ecm 500 800 500 500 1000 500 3000

R1 0 1 2 2 0 5 2 0

R2 7 4 2 3 0 6 2 8

R3 10 3 3 11 0 5 0 19

R4 1 0 1 2 2 0 0 8


The Specific R1 Items

• TESLA

• JLC-C

• NLC/JLC-X

• CLIC



• TESLA

• JLC-C

• NLC/JLC-X

• CLIC

• Ecm = 800 GeV Building and testing of a cryomodule at 35 MV/m and measurements of dark current

•Requires the module test stand

•Delayed by budget constraints

•Very unlikely to happen before 2005!However, the push to Ez>35 MV/m

continues…


TESLA High-Gradient R&D

• High gradients good for X-Ray FEL too




• Electro-polishing programme on-going and considered best for mass-production

1,0E+09

1,0E+10

1,0E+11

0 5 10 15 20 25 30 35 40Eacc [MV/m]

Q0

TESLA 800 goal




• Electro-polishing programme on-going and considered best for mass-production

• Fast piezo cavity tuner to compensate Lorentz force detuning

Beam on



• TESLA

• JLC-C

• NLC/JLC-X

• CLIC

• Ecm = 500 GeV High power tests of of C-band choke-mode and dark current

• Ecm = 500 GeV Demonstration of SLED-II pulse compressor at full power



• TESLA

• JLC-C

• NLC/JLC-X

• CLIC

• Ecm = 500 GeV Test of complete accelerator structure at design gradient with detuning and damping, including study of breakdown and dark current

• Ecm = 500 GeV Demonstration of SLED-II pulse compressor at full powerGoal: end of 2003 for proof of principle tests



• TESLA

• JLC-C

• NLC/JLC-X

• CLIC

• Test existing structures at 130ns pulse length and design gradient.

• High power tests of structures with wakefield damping

• design and test of switchable power extraction transfer structures

• Validation of drive beam generation with fully loaded linac

• full test of a basic hardware unit (at reduce length)Many basic questions as expected for an R&D project


The R2 Items

• Damping Rings– Electron cloud effects– fast ion instabilities– Extraction kicker stability– Tuning simulations

• LET– Static tuning studies– girder/cryomodule prototypes

to study stability (vibration)– Critical beam instrumentation

• Reliability– Detailed evaluation of critical

sub-systems reliability

Common items related to all designs


TESLA R2• Test of complete main linac RF sub-unit

(as described in TDR) with beam• Tests of several cryomodules running at gradient

23.4 MV/m for a prolonged period of time– quench rates, breakdowns, dark currentT

TF-

II,

X-F

EL


TESLA R2• Test of complete main linac RF sub-unit

(as described in TDR) with beam• Tests of several cryomodules running at gradient

23.4 MV/m for a prolonged period of time– quench rates, breakdowns, dark current

• One versus two tunnels (reliability)• DR dynamic aperture

– wiggler end fields– need to minimise injection losses

(Pinj=220kW)• DR kicker development• Head-on versus crossing angle

– extraction lines issues


JLC-X/NLC R2

• Test of complete X-band main linac RF sub-

unit (as described in baseline design) with

beam

• Full test of KEK 75 MW 1.6s PPM klystron at

150/120 Hz

• Full test of SLAC induction modulator


8-Pack Project

• Used 450MW klystrons

• Drive NLC ready structures in NLCTA

• End 2003


R3

• To some extent fine tuning R2 requirements

• Much detailed work which (eventually) must be done

• Examples (TESLA):– Backgrounds and collimation– Impact of positron scheme on

commissioning/operability– LLRF (needs to be ‘robust’)– single tunnel noise sources


The Positive Side

Rankings reflect the concerns of the working groups

But TRC overall findings were extremely positive

“did not find any insurmountable obstacle to building TESLA, JLC-C, JLC-X/NLC within the next few years…”

executive summary

The ILC-TRC


The Positive Side



“also noted that the TESLA linac RF technology for 500 GeV c.m. is the most mature.”

executive summary

The ILC-TRC


The Positive Side



Assuming the R1s are demonstrated (hopefully) by the end of 2003, the RF systems of the two machines will be on an equal footing…

executive summary

The ILC-TRC concluded that


The Positive Side



At that time, the HEP community should make a choice based on the technical differences of the two machines reflected by the R2 issues

executive summary

The ILC-TRC concluded that


The Manpower & Money Problem

The R1-4 issues are important but they need money and manpower to resolve

The TESLA collaboration has limited (sub-critical) resources to address the R2 items (not related to the linac technologies) on any immediate time scaleX-FEL has linac technology in hand


Final Comments

• The TRC is a excellent example of what we can achieve when the LC accelerator communities work together

• Attempts to maintain the ‘momentum’ post TRC are dwindling

• Need guidance (mandate?) from ILCSC and the support of lab management to continue this collaborative work

• Need More People!

nick walkerecfa-desy nikef amsterdam 4.04.2003 international linear collider technical review...

Documents

lilje desy

decking desy

weise desy

gev slide

ilc trc

wilson slac slide

operability slide

talk slide