Nick WalkerECFA-DESY NIKEF Amsterdam International Linear Collider Technical Review Committee Nick Walker (DESY)

Nick WalkerECFA-DESY NIKEF Amsterdam Where is The Report? Available online: Printed and CD-ROM versions should be available soon (now?) 420 pages!

Nick WalkerECFA-DESY NIKEF Amsterdam 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 : ICFA requests that ILC-TRC reconvene to produce a second report (subject of this talk)

Nick WalkerECFA-DESY NIKEF Amsterdam 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

Nick WalkerECFA-DESY NIKEF Amsterdam Second ILC-TRC Charge To assess the potential of each design for reaching higher energies above 500 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

Nick WalkerECFA-DESY NIKEF Amsterdam LC Status at First TRC TESLASBLCJLC-SJLC-CJLC-XNLCVLEPPCLIC f [GHz] L  [cm -2 s -1 ] P beam [MW] ~1-4 P AC [MW]  y [  m]  y * [nm] E cm =500 GeV

Nick WalkerECFA-DESY NIKEF Amsterdam LC Status at Second TRC TESLASBLCJLC-SJLC-CJLC-X/NLCVLEPPCLIC f [GHz] L  [cm -2 s -1 ] P beam [MW] P AC [MW]  y [  m] 3441  y * [nm] E cm =500 GeV

Nick WalkerECFA-DESY NIKEF Amsterdam Organisation Chair Greg Loew (SLAC) Reinhard Brinkmann (DESY) Kaoru Yokoya (KEK) Tor Raubenheimer (SLAC) Gilbert Guignard (CERN) Steering Committee WG I Technology, RF Power, and Energy Performance Assessment WG II Luminosity Performance Assessment

Nick WalkerECFA-DESY NIKEF Amsterdam Organisation Chair Greg Loew (SLAC) Steering Committee WG I Technology, RF Power, and Energy Performance Assessment WG II Luminosity Performance Assessment WG III Reliability, Availability and Operability

Nick WalkerECFA-DESY NIKEF Amsterdam 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 Chair Daniel Boussard (CERN) Members C. 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)

Nick WalkerECFA-DESY NIKEF Amsterdam Luminosity Working Group e ± Sources (gun  DR) DR Low Emittance Transport (LET, from DR  IP) –bunch compressors –main linac –beam delivery Machine Detector Interface Chair Gerry Dugen (Cornell) Members R. 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!

Nick WalkerECFA-DESY NIKEF Amsterdam Reliability Working Group Reliability –hardware components –MTBF Availability –fraction of time available for delivering luminosity Operability –impact of (invasive) tuning, machine studies etc. Members C. 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-Chairs Ralph Pasquinelli (FNAL) Nan Phinney (SLAC) technology luminosity

Nick WalkerECFA-DESY NIKEF Amsterdam nd 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 !)

Nick WalkerECFA-DESY NIKEF Amsterdam 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

Nick WalkerECFA-DESY NIKEF Amsterdam The Rankings for R&D Ranking 1 Ranking 2 Ranking 3 Ranking 4

Nick WalkerECFA-DESY NIKEF Amsterdam The Rankings for R&D 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)

Nick WalkerECFA-DESY NIKEF Amsterdam The Rankings for R&D 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

Nick WalkerECFA-DESY NIKEF Amsterdam The Rankings for R&D 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)

Nick WalkerECFA-DESY NIKEF Amsterdam The Rankings for R&D 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

Nick WalkerECFA-DESY NIKEF Amsterdam Rankings Score Sheet TESLAJLC-CJLC-X/NLCCLIC Common E cm R R R R

Nick WalkerECFA-DESY NIKEF Amsterdam The Specific R1 Items TESLA JLC-C NLC/JLC-X CLIC

Nick WalkerECFA-DESY NIKEF Amsterdam The Specific R1 Items TESLA JLC-C NLC/JLC-X CLIC E cm = 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 E z >35 MV/m continues…

Nick WalkerECFA-DESY NIKEF Amsterdam TESLA High-Gradient R&D High gradients good for X-Ray FEL too

Nick WalkerECFA-DESY NIKEF Amsterdam TESLA High-Gradient R&D High gradients good for X-Ray FEL too Electro-polishing programme on-going and considered best for mass- production TESLA 800 goal

Nick WalkerECFA-DESY NIKEF Amsterdam TESLA High-Gradient R&D High gradients good for X-Ray FEL too Electro-polishing programme on-going and considered best for mass- production Fast piezo cavity tuner to compensate Lorentz force detuning Beam on

Nick WalkerECFA-DESY NIKEF Amsterdam The Specific R1 Items TESLA JLC-C NLC/JLC-X CLIC E cm = 500 GeV High power tests of of C-band choke-mode and dark current E cm = 500 GeV Demonstration of SLED-II pulse compressor at full power

Nick WalkerECFA-DESY NIKEF Amsterdam The Specific R1 Items TESLA JLC-C NLC/JLC-X CLIC E cm = 500 GeV Test of complete accelerator structure at design gradient with detuning and damping, including study of breakdown and dark current E cm = 500 GeV Demonstration of SLED-II pulse compressor at full power Goal: end of 2003 for proof of principle tests

Nick WalkerECFA-DESY NIKEF Amsterdam The Specific R1 Items 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

Nick WalkerECFA-DESY NIKEF Amsterdam 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

Nick WalkerECFA-DESY NIKEF Amsterdam 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 TTF-II, X-FEL

Nick WalkerECFA-DESY NIKEF Amsterdam 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 (P inj =220kW) DR kicker development Head-on versus crossing angle –extraction lines issues

Nick WalkerECFA-DESY NIKEF Amsterdam 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 1.6  s PPM klystron at 150/120 Hz Full test of SLAC induction modulator

Nick WalkerECFA-DESY NIKEF Amsterdam Pack Project Used 4  50MW klystrons Drive NLC ready structures in NLCTA End 2003

Nick WalkerECFA-DESY NIKEF Amsterdam 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

Nick WalkerECFA-DESY NIKEF Amsterdam 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

Nick WalkerECFA-DESY NIKEF Amsterdam The Positive Side Rankings reflect the concerns of the working groups But TRC overall findings were extremely positive “also noted that the TESLA linac RF technology for 500 GeV c.m. is the most mature.” executive summary The ILC-TRC

Nick WalkerECFA-DESY NIKEF Amsterdam The Positive Side Rankings reflect the concerns of the working groups But TRC overall findings were extremely positive 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

Nick WalkerECFA-DESY NIKEF Amsterdam The Positive Side Rankings reflect the concerns of the working groups But TRC overall findings were extremely positive 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

Nick WalkerECFA-DESY NIKEF Amsterdam 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 scale X-FEL has linac technology in hand

Nick WalkerECFA-DESY NIKEF Amsterdam 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!