27 th May 2009 CLIC ACE meetingL. Rinolfi CLIC Main Beam generation Baseline configuration only L. Rinolfi for the CLIC Injector complex team

27 th May 2009 CLIC ACE meetingL. Rinolfi The CLIC Main Beams generation is focused on 3 studies to produce the bunch charge at the entrance of the Pre-Damping Ring (PDR) : 1) Base Line configuration: 3 TeV (c.m.) - polarized electrons (4.4x10 9 e - /bunch) and unpolarized positrons (6.7x10 9 e + /bunch). R&D program for the CDR 3) Double charge configuration: 500 GeV (c.m.) - polarized electrons (8x10 9 e - /bunch) and unpolarized positrons (13x10 9 e + /bunch). 2) Polarized positron configuration: 3 TeV (c.m.) - polarized e - and e + with same charge as above An huge R&D work is ongoing for polarized e + but not presented in this talk

27 th May 2009 CLIC ACE meetingL. Rinolfi e - gun Laser DC gun Polarized e - Pre-injector Linac for e MeV e - /  Target Pre-injector Linac for e MeV Primary beam Linac for e - 5 GeV Injector Linac 2.66 GeV e + DR e + PDR Booster Linac 5.14 GeV 4 GHz e + BC1 e - BC1 e + BC2 e - BC2 e + Main Linac e - Main Linac 2 GHz e - DR e - PDR 2 GHz 4 GHz 12 GHz 8 GeV 48 km 2.86 GeV  e  Target AMD 2.86 GeV 3 TeV Base line configuration CLIC Main Beam Injector Complex in 2009 IP

27 th May 2009 CLIC ACE meetingL. Rinolfi NLC (1 TeV) CLIC 2008 (3 TeV) CLIC 2008 (0.5 TeV) ILC (0.5 TeV) EGeV88815 N nbnb tbtb ns (6 RF periods) t pulse ns  x,y nm, nm3300, 30600, , , 24 zz mm EE  0.68 (3.2 % FW) f rep Hz PkW CLIC Main Beam nominal parameters At the entrance of the Main Linac for e - and e +

27 th May 2009 CLIC ACE meetingL. Rinolfi 0.5 FTE (Staff) FTE (Fellow) CERN manpower for the beam generation studies

27 th May 2009 CLIC ACE meetingL. Rinolfi CountriesInstitutesContact person SubjectStatusDate FranceLALA. Variolae+ studiesFormal agreementSeptember 2008 GermanyFZR RossendorfJ. TeichertCompton sourcesIn preparationNovember 2008 JapanKEKT. Omorie+ studiesInformal agreementOctober 2007 JapanKEKJ. UrakawaR&D on targets systems and experiments at KEKB In preparationJanuary 2009 TurkeyAnkara UniversityA.Kenan ÇiftçiFLUKA simulationsInformal agreementApril 2009 UkraineKharkov InstituteE. BulyakCompton RingsInformal agreementApril 2006 United KingdomCockcroft InstituteJ. Clarkee+ studiesFormal agreementOctober 2008 USAArgonne LaboratoryW. Gaie+ studiesIn preparationJanuary 2009 USAJefferson LaboratoryM. PoelkerPolarized e-Formal agreementSeptember 2007 USASLACJ. SheppardPolarized e-In preparationAugust 2008 Alphabetic order for countries External collaborations

27 th May 2009 CLIC ACE meetingL. Rinolfi Generation of polarized electron

27 th May 2009 CLIC ACE meetingL. Rinolfi Specific issues for polarized e - source ParameterSymbol0.5 TeV3 TeV Number Electrons per microbunchNeNe 10 x x 10 9 Number of microbunchesnbnb Width of microbunchtbtb ~ 100 ps Time between microbunches tbtb ns Microbunch rep ratefbfb 1999 MHz Width of macropulseTBTB 177 ns56 ns Macropulse repetition rateFBFB 50 Hz Charge per micropulse (e x N e )CbCb 1.6 nC0.96 nC Charge per macropulse (C b x n b )CBCB 566 nC300 nC Average current from gun (C B x F B )I ave 28 μA15 μA Average current in macropulse (C B / T B )IBIB 3.2 A1.9 A Duty Factor w/in macropulse (t b /  t b ) DF0.2 Peak current of micropulse (I B / DF)I peak 16 A9.6 A Current density (I peak /  ) [spot size radius 1 cm] D5 A/cm 2 3 A/cm 2 laser & gun photo cathode One of the critical issues is the Surface charge limit => needs demonstration => depends on laser system

27 th May 2009 CLIC ACE meetingL. Rinolfi ParametersILCCLIC 0.5 TeV CLIC 3 TeV Electrons/microbunch~3E1010E96E9 Number of microbunches Width of Microbunch1 ns~100 ps Time between microbunches~360 ns500.2 ps Width of Macropulse1 ms177 ns156 ns Macropulse repetition rate5 Hz50 Hz Charge per macropulse~12600 nC566 nC300 nC Average current from gun63  A28  A15  A Peak current of microbunch4.8 A16 A9.6 A Current density (1 cm radius)1.5 A/cm 2 5 A/cm 2 3 A/cm 2 Polarization>80% ILC and CLIC e - sources

27 th May 2009 CLIC ACE meetingL. Rinolfi CLIC Electron Beam Demo J. Sheppard/SLAC at TILC09 workshop Goals: The major goals for photocathode development at SLAC for the ILC and CLIC are: 1) demonstration of full charge production without space charge and surface charge limitation; 2) >85% polarization; 3) ~1% QE and long QE lifetime. Formal CERN/SLAC collaboration under discussion for this topic

27 th May 2009 CLIC ACE meetingL. Rinolfi 1) Assuming that SLAC management would agree with the proposed demonstration and provides support, then preliminary tests are expected before September If existing equipments show some limitations, the idea is to make the appropriate corrections in In this case, results and relevant issues will be included in the CDR. 2) Further along ( ), the SLAC cathode and laser would be installed together with JLab HV gun. Possible schedule

27 th May 2009 CLIC ACE meetingL. Rinolfi Generation of unpolarized positron

27 th May 2009 CLIC ACE meetingL. Rinolfi Primary electron beam ParameterUnit Primary e - Beam EnergyGeV5 N e - /bunch N bunches / pulse-312 N e - / pulse Pulse lengthns156 Repetition frequencyHz50 Beam powerkW94 Beam radius (rms)mm2.5 Bunch length (rms)mm0.3 e - /  Target 2 GHz Primary beam Linac for e - 5 GeV  e  Target e - gun

27 th May 2009 CLIC ACE meetingL. Rinolfi Unpolarized e + based on hybrid targets Electron beam on the crystal: - energy = 5 GeV - beam spot size = 2.5 mm crystal amorphous e-e- e-e- e+e+ First target is a crystal: 1.4 mm thick W oriented along axis where channeling process occurs Second target is amorphous: 10 mm thick W  Charged particles are swept off after the crystal: only  (> 2MeV) impinge on the amorphous target. The distance between the two targets is 3 meters e-e- e+e+ After several simulations, an optimized configuration is given below:

27 th May 2009 CLIC ACE meetingL. Rinolfi Results just downstream the e + target Blue: after the target Red: after the AMD (*) (*) AMD = Adiabatic Matching Device: B 0 = 6 T, L = 50 cm,  = 22m -1 Yield = 2.1 e + / e - Max energy = 1.9x10 9 GeV / mm 3 Peak Energy Density Deposition PEDD = 15.5 J/g O. Dadoun / LAL Experimental limit found at SLAC: with a PEDD  35 J/g => target does not survive

27 th May 2009 CLIC ACE meetingL. Rinolfi Beam power and PEDD crystal amorphous e-e- e-e- e+e+  e-e- e+e+ ParameterUnit TargetCrystalAmorphous MaterialWW Lengthmm1.410 Beam power depositedkW Deposited P / Beam Power%0.28 Energy lost per volume10 9 GeV/mm Peak energy deposition density (PEDD)J/g

27 th May 2009 CLIC ACE meetingL. Rinolfi e + source for CLIC 500 GeV Primary beam Linac for e - 2 GHz e - /  Target 2 GHz  e  Target AMD RF gun e - /  Target 2 GHz  e  Target AMD Pre-injector Linac for e MeV Pre-injector Linac for e MeV 5 GeV To injector linac Double charge / bunch => Double PEDD =>  breakdown limit => Double target station

27 th May 2009 CLIC ACE meetingL. Rinolfi Pre-Injector Linac for e + ACS 1 ACS 2 G  10 MV/m L = 1.8 m ACS 12 ACS 11 FC Target E = 200 MeV Solenoids Accelerating Structures (ACS): Magnetic Field of Flux Concentrator (FC)T6 FC Lengthm0.5 Solenoid Magnetic FieldT0.5 Length of Pre-Injector Linacm42 Radius = m f = 2 GHz e+e+  Yield: 0.9 e + / e 200 MeV

27 th May 2009 CLIC ACE meetingL. Rinolfi Pre-Injector Linac ParameterUnit CLIC 2009 (A. Vivoli) EGS4 + ASTRA Energy (E)GeV0.2 No. of particles/bunch (N) Bunch length (rms) (  z ) mm10 Energy Spread (rms) (  E ) %8 Longitudinal emittanceeV.s0.5 x H and V emittances (  x ) mm. mrad6700 Longitudinal Transversal

27 th May 2009 CLIC ACE meetingL. Rinolfi "ILC/CLIC e + generation" working group J. Clarke (Daresbury), L. Rinolfi (CERN) Officially set-up at ILC08 workshop Chicago: 15 th - 20 th November 2008

27 th May 2009 CLIC ACE meetingL. Rinolfi CLIC/ILC work plan (1) Undulator-based source Develop Geant4 model of collimator, target, capture optics, and capture RF assembly. Optimise parameters wrt yield, polarisation and cost (Collaboration with ANL). Consider timing constraints issues and upgrade paths. Consider electron beam quality issues. Compton source Design of the Compton ring (Collaboration with NSC KIPT). Optical stacking cavity (Collaboration with LAL and KEK). High power lasers. Stacking simulations. Lithium lens capture optics Evaluate suitability for Undulator and Compton schemes (Wide collaboration needed). Conventional sources (Conventional targets and hybrid targets) Simulations to optimize the unpolarized e+ yield (Collaboration with LAL). Evaluate the applicability of the Li lens. Electron source Set-up the CERN, CI, JLAB, SLAC collaboration for tracking studies. Preliminary tests at HV for the DC gun. Short-term plan mid-2009

27 th May 2009 CLIC ACE meetingL. Rinolfi Undulator-based source Consider optimal target technology: thermal load, shock waves, activation (Collaboration with LLNL). Compton source Extend Geant4 model to Compton source (Collaboration with LAL) Stacking simulations studied in 6D. Lithium lens tests Participate to the BINP tests and CesrTA tests. Conventional sources Channelling measurements on NA63 experiment at CERN Perform experiments at KEKB positron source. Electron source Perform tracking studies (Collaboration with JLAB and SLAC). Hardware tests at JLAB and SLAC for the DC gun at very HV. CLIC/ILC work plan (2) Long-term plan mid

27 th May 2009 CLIC ACE meetingL. Rinolfi Summary 1) For the Base Line configuration at 3 TeV, polarized e - and unpolarized e + would be generated close to the requested performance but extensive simulations for both sources, in parallel with an important R&D program, remain to be done to confirm the present studies. 2) Double charge configuration (0.5 TeV): for the polarized electrons, the space charge limit is a real challenge to provide the requested charge pattern; for the positrons, it would require a double target stations under the present conditions. 3) For polarized positrons, extensive studies are carried on, in collaboration with several institutes. For the 3 TeV, several major issues remain to be investigated and demonstrated by simulations. 4) The beam intensity stability of both sources could be a performance issue.