1. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 1.Why? 2.LHeC Physics – some snapshots 3.Machine 4.Experiment 5.When: Towards a CDR with and for the LHeC steering group LHeC Status John Dainton Cockcroft Institute and Univ Liverpool, Daresbury Science and Innovation Campus, GB http://www.lhec.org.uk

2. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 1.Why?

3. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why? The Energy Frontier quarks neutral currents singlet e R asymptotic freedom Drell Yan charm W,Z jets charm 3 colours gluon lh e+e-e+e- pp SU(2) L x U(1) QCD  1968-1986

4. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why? The Energy Frontier spacelike EW strong interaction high density QCD c,b in hadrons (HERA) νmass b quark t quark M W (TeVatron) M Z, sin 2 θ, 3 ν h.o. EW (t,H ?) (LEP/SLC) CKM (B-factory) lh e+e-e+e- pp Standard Model  1986-2010 Fermi scale

5. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why? The Energy Frontier TeVdiscovery & precision ? particles ? symmetries ? dense QCD (LHeC) TeV discovery ? Higgs? new particles? new symmetries? (LHC) tt discovery & precision ? spectroscopy Higgs ? (ILC/CLIC) lh e+e-e+e- pp Beyond Standard Model new physics  2008-2033 ? Terascale -

6. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why? The Matter Frontier QCD dof @ extremes strong QCD  1 C (LHeC) QGP ? QCD phase equilibria? nuclear dynamics? nuclear formation (LHC) pQCD (ILC/CLIC) leptonA e+e-e+e- AA matter creation new physics  2008-2033 ? chromodynamic creation ?

7. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why: Leptons  Quarks ? how are leptons and quarks related ? put them together at the highest energy in the finest detail ICHEP76 Tblisi

8. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Chadwick Cambridge nucleus nucleon quark NC+CC+gluon ● LHeC g+EW ? ● unique chiral probe @ 0.0001 fm ? ● protons+neutrons Manchester SLAC ● 70 e ±  p 7000 GeV cm energy < 1.4 TeV SM + new Lq physics @ ~ 0.0001 fm ? SM + new Lq physics @ ~ 0.0001 fm ? Lepton+quark @ TeV  Z W ee RL ? e±e± am? Q2Q2 s eq

9. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why: Structure @TeV Chadwick Cambridge nucleus nucleon ● unique chiral probe @ 0.0001 fm ? ● protons+neutrons Manchester Q 2 y x ee ee quark NC+CC+gluon ● LHeC g+EW ? SLAC SM + q structure @ ~ 0.0001 fm ? SM + q structure @ ~ 0.0001 fm ? QCD

10. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Why? The Scope discovery + precision @ Terascale precision structure and dynamics @ LHC TeV scale nuclear structure & dynamics @ 100s GeV very dense matter

11. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 - s eq ≤ (4000 GeV) 2 in ~ 0.1 am ! - s eq ~ (300 GeV) 2 in ~ 0.7 am s eq >TeV LHeC TeV eq Kinematic Reach space-like >TeV 3×10 -7 - Q 2 ≤ 30,000 GeV 2 ● 2007: HERA - Q 2 ≤ 4×10 6 GeV 2 ● ≥20..?: LHeC e±e± RL am? Q2Q2 s eq

12. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Most of the mass of ordinary matter is concentrated in protons and neutrons. It arises from …[a]… profound, and beautiful, source. Numerical simulation of QCD shows that if we built protons and neutrons in an imaginary world with no Higgs mechanism - purely out of quarks and gluons with zero mass - their masses would not be very different from what they actually are. Their mass arises from pure energy, associated with the dynamics of confinement in QCD, according to the relation m = E/c 2. This profound account of the origin of mass is a crown jewel in our Theory of Matter. Frank Wilcek CERN October 11, 2000 Why: Dense Colour ? probe hadronic matter at highest parton density

13. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 QCD is headline stuff ! ● found on a Guardian newsaper web page ●found on Frank Wilcek’s blackboard

14. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 QCD Field Energy Density - x Bj ≥ 5×10 -5 -x Bj ≥ 5×10 -7 TeV ep Kinematic Reach space-like >TeV s eq >TeV - Q 2 ≥ 1 GeV 2 ● 2007: HERA LHeC x Q 2 y e±e± e±e± - Q 2 ≥ 1 GeV 2 ● ≥2016?: LHeC 3×10 -7

15. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ● ≥20..?: LHeC -x Bj ≥ 5×10 -7 Gluon recombination x Q 2 y ee ee low x large nuclei - Q 2 ≥ 1 GeV 2 Q 2  size of gluons x Bj  phase space for gluons p and A

16. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 2.LHeC physics - some snapshots 2.LHeC physics - some snapshots

17. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Lepton+quark @ TeV LHC LHeC SM (hadronic) + signal Lq & LqLq production σ ~ few × 0.1 fb (Λ=0.1) SM (electroweak) + signal Lq formation σ ~ 100 fb (Λ=0.1) ● leptoquark systems – new physics + SM Re + resonance

18. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Lepton+quark @ TeV ● leptoquark systems – new physics +SM 1 TeV LHeC ×10 -3 ↓ LHC LHeC LHC

19. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 experim l signature e, q e+ F=0 e- F=2 qq  g  Lq Lq production mechanism ? disentangle mass spectrum ? e q e q ** LHC Lq pairs+decayLHeC Lq formation+decay fermion number e+ e- q or q ? _ _ _ _ Lepton+quark @ TeV spin parity and chirality defined formation (e LR )  precision BRs (NC CC) inclusive coherence unique PWA SM + signal + interference jets + leptons jet+lepton+p T balance jet +p T imbalance

20. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 experim l signature e, q e+ F=0 e- F=2 gq  Lq l production mechanism ? disentangle mass spectrum ? e q e q ** LHC Lq +decayLHeC Lq formation+decay fermion number _ spin parity and chirality defined formation (e LR )  precision BRs (NC CC) inclusive coherence unique PWA SM + signal + interference jet + leptons jet+lepton+p T balance jet +p T imbalance Lepton+quark @ TeV

21. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ● precision  extrapolation  discovery probe new chromodynamic physics – beyond SM ? ● short distance structure of SM+ - 2007  @ 10 -3 ppm - 2007 G F @ 10 ppm - 2007 G @ 0.1% - 2007 α S @ 1-2% - LHeC + detector  α S @ few ‰ precision  QCD at highest energy Unification ?

22. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Lepton-Parton and Parton-Parton ?  Z W ee RL ? ? g q ? ? ep  eX pp  (jet+jet)X probe-parton jet LHeC energy scale: 70  7000 GeV pp energy scale: 7000  7000 GeV x probe/p = 0.01 probe+p at LHeC scale probe = e 

23. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 LHC probe parton - xq = xU +xD +xU +xD g :q ~ 2:1 mixed ● probe-parton @ x  0.01 ● probe-parton @ x » 0.01 g :q  0 all quark “mixed” LHC probe @ LHeC energy q LHC probe @ LHC top energy - -

24. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Gluon recombination @ HERA ● relentless rise of quark (F 2 ) and gluon ∂F 2 / ∂lnQ 2 ● low-x rise of F 2 - HERA: precision @ x > 10 -4 @ Q 2 =10 GeV 2

25. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Gluon recombination @ LHeC (Jeff Forshaw) (10 fb -1 ) HERA ● low-x rise of F 2 - LHeC: precision @ x > 10 -4 @ Q 2 =250 GeV 2 stat 0.1% sys 2-3% ● LHeC “nails” saturation

26. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Gluon recombination @ LHeC ● ep saturation Q 2 ≤ 5 GeV 2 eA saturation Q 2 ≤ 20 GeV 2 ● LHeC “nails” saturation

27. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Partons in Nuclear Matter ● fundamental to origin of mass in Universe (Wilczek) - from nucleon valence to QCD-field dominated (x  ) - increasing number of valence partons (A  ) ● very limited, but tantalising, old data - Q 2 0.01

28. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 DGLAP 1 C dynamics in p and A ● low-x reach at LHeC precision @ x > 10 -4 @ Q 2 =250 GeV 2 (x =βx I ) ● low x physics of P P in P: triple R QCD  reggeon calculus ? I P P @ low-β III LHeC ? I HERA

29. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 1 C dynamics in p and A ● low-x P physics at LHeC I ● LHeC diffraction “nails” saturation

30. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 1 - “vacuum” physics 1 C dynamics in p and A ● P physics at LHeC 0 + “vacuum” physics I ●  * P physics @ 100 GeV I ● e P physics @ > 100 GeV: leptopomerons ? I ● rapidity ≤ 5 θ ≤ few o ILC e + e -

31. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 3.Machine

32. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Proton beam ● ”standard” LHC protons protons antiprotons protons N p ε pN … with electrons? protons electrons?

33. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 LHC ● e-ring - bypass experiments and RF ?

34. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ep Collisions ● after B physics @ LHC ? ep alongside pp data-taking @ LHC p e civil engineering tunnel >2×250m×2m Ø @IP civil engineering tunnel >2×250m×2m Ø @IP LHeC F Willeke (DESY and BNL)

35. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Luminosity: e-Ring 100 mA klystron + SR 10 33 cf also A.Verdier 1990, E.Keil 1986 ● e-ring - 10 33 cm -2 s -1 - E e < 80 GeV - power P < 60 MW - ERL  10 34 cm -2 s -1 ? (eRHIC)

36. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 e-Ring IR simultaneous pp (AA) and ep (eA)

37. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 e-ring First p beam lens: septum quadrupole. Cross section and Field calculation Synchrotron radiation fan and HERA type absorber 100W/mm 2 cf also W.Bartel Aachen 1990

38. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 e-ring Issues  power: 25 ns  nx40 MHz RF I < 100 mA 60 klystrons @ 1.3MW, coupler 0.5MW, 66% effy extra RF in bypasses  injection: 1.4x10 10 e in 2800 bunches (LEP2 4x10 11 in 4) energy < 20 GeV (ELFE, KEK …)  SR  LHC magnets: water cooling+Pb  bypasses: ATLAS CMS + RF  ~500m from arcs ~ -20cm radius of e-ring  space: above LHC

39. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Circulating LHC beams pass in between support feet Kicker magnet installed on beam dump line above LHC Equipment above installed LHC beamlines….

40. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ● L LHeC e ± p eA @ 0.00014 fm ● L LHeC e ± p eA @ 0.00014 fm e ± p Luminosity ● astounding ! ● ×10 2 L NMC μp @ 0.01 fm ● ×10 2 L NMC μp @ 0.01 fm ● L eRHIC e pol p pol eA @ 0.007 fm ● L eRHIC e pol p pol eA @ 0.007 fm indisputably a next step ? ● ×10 2 L HERA e pol p @ 0.001 fm ● ×10 2 L HERA e pol p @ 0.001 fm ×10

41. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 e-linac + LHC alternative sites 6km S. Chattopadhyay (Cockcroft), F.Zimmermann (CERN), et al. D Brandt (CERN), F.Zimmermann (CERN), et al. “QCD Explorer”

42. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Luminosity: Linac-Ring  I e = 100 mA High cryo load to CW cavities ● e-linac - 10 32 cm -2 s -1 ~HERA - E e < 140 GeV ($s) - power P < 60 MW - 6 km+gaps @23 MV/m lumi + energy horizon s = (2 TeV) 2

43. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Linac-Ring & Ring-Ring L-R R-R Energy / GeV 40-140 … 40-80 Luminosity / 10 32 cm -2 s -1 0.5 10 Mean Luminosity, relative 2 1 [dump at L peak /e] Lepton Polarisation 60-80% 30% [?] Tunnel / km 6 2.5=0.5 * 5 bypasses Biggest challenge CW cavities Civil Engineering Ring+Rf installation Biggest limitation luminosity (ERL,CW) maximum energy IR not considered yet allows ep+pp one design? (eRHIC) 2 configurations [lox, hiq]

44. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Machine ● ring-ring - stupendous lumi (~ LHC) - energy horizon ~ 1.2TeV - civil engineering impact on LHC - e-polarisation (Sokolov-Ternov) - ep (eA) with pp (AA) ● LHC upgrade: cost ? ● linac-ring - moderate (~HERA) lumi (~ LHC) - energy horizon ~ multi-TeV - less civil engineering impact on LHC - e-polarisation (source: e + ?) - ep (eA) with pp (AA)

45. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Linac EBIS Booster AGS RHIC IP#12 - main Coherent Electron Cooling Four multiple passes: vertical separation of the arcs Ø1.22 km Main beneficiary from the cooling of hadron beams Reduction of the hadron bunch length shortens vertex It also reduces e-beam disruption Emittance reduction provides for proportional reduction of the electron beam current (less X-ray back-ground in the detector, higher energy eRHIC above 20 GeV, ….) The reduction of emittance and bunch length allow reduction of  * to few cm from present 25 cm and corresponding increase would push e - -p luminosity to 10 34 cm -2 s -1 (  * =10 cm) and above eRHIC and ERL V Litvinenko (BNL)

46. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 eRHIC eRHIC loop magnets 5 mm 20 GeV e-beam 16 GeV e-beam 12 GeV e-beam 8 GeV e-beam Common vacuum chamber 5 mm Small gap provides for low current Very low power consumption magnets C- Dipole C-Quad V Litvinenko (BNL)

47. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Bargman, Mitchel,Telegdi equation Gun ERL spin transparency Total angle Has solution for all energies! n passes n=2 V Litvinenko (BNL)

48. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Ring-Ring LHeC is limited by power of synchrotron radiation from the e-beam! M.Klein, ecfa07 talk

49. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 M.Klein, ecfa07 talk For linac-ring LHeC a pulsed linac with 0.5% duty factor (1 msec, 5 Hz) without energy recovery considered

50. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ERL based LHeC Electrons Protons Cooling/no Cooling Energy140 GeV7 TeV N per bunch 0.088 10 11 1.7 10 11 Rep rate, MHz 40 Beam current, mA 5.61090 Norm emittance,  m 60.3 / 3.8  *, m 1.30.5 *D*D 6.3.14 0.0006/ 0.0001 Luminosity, x 10 34 cm -2 sec -1 0.24 / 0.06 Loss for SR, MW67Kink  =0.03 Hard radiation may be a problem

51. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ERL based LHeC Luminosity 3. 10 34 cm -2 sec -1 at all energies of e-beam (probably will be limited by burn-off of the proton beam) Or “ ring-ring” luminosity of 10 33 cm -2 sec -1 with 3 mA electron beam current and 2.2 MW loss for SR e-beam current is low (because of the cooling!) If further reduction of  * is possible, L~ 10 35 is feasible Higher energies of electrons are possible e-Beams with very low emittance are possible -> larger  * for electron - easier optics, longer detectors, less synch modulation effects…. 140 GeV, 5 mA e-beam and luminosity of 4. 10 33 cm -2 sec -1 Tiny beam pipe to “thru-pass” pp IR regions ? V Litvinenko (BNL)

52. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Low e-current Normalized emittance of electrons ~ 3  m is possible - no problems to match the proton beam @ 100 GeV,  e =2 10 5 ~ 300  p, i.e. proton normalized emittance can be as low a 0.01  m N e ~  norm ~  norm : 3.8  m -> 0.1  m : N e =4 10 9 I e = 20 mA, SR loss =57 MW (the same as Ring- Ring with 100 x luminosity!) V Litvinenko (BNL)

53. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Other considerations May (for the most part) fit inside the LHC tunnel. Tiny e beam pipe to thru-pass pp IRs ? V Litvinenko (BNL)

54. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Is there room for linac in the straights? Other considerations V Litvinenko (BNL)

55. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008  ERL seems to be the most promising approach for high energy, high luminosity electron-ion and polarized electron-proton collider  It can take advantage of any ring-ring concept and go further  Presently there is no show-stoppers but a significant amount of R&D  At BNL the R&D ERL tests in 2009, MIT’s progress with developing high current polarized gun, prototyping of small gap magnets will next step-stones towards QCD factory at BNL.  LHeC based on this principle reach 10 34 -10 35 level of luminosity Conclusions: ERL V Litvinenko (BNL)

56. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 4.Experiment

57. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Sensitivity 100 fb -1 70 GeV e-ring 1 fb -1 HERA (sim) Neutral Current ep ->eX Charged Current ep -> X 10 fb -1 140 GeV e-linac ● rates: energy can win you TeV 2 in Q 2

58. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 IR and Experiment ● IR ±many m ● IR ≥9.4 o around beam

59. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 electron Asymmetric Collider quark p 7 TeVe 70-140 GeV ● asymmetric beam momenta: LHeC ~ TeV ● ”forward” hemisphere detection to multiTeV topological challenge precision challenge quads for TeV ? ● ”backard” hemisphere detection to fewx10 GeV

60. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 IR Kinematics backward e forward remnant 1 C forward TeV hadrons

61. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ep is precision @ every scale precision @ TeV scale of lepton+quark eq νq τqcf HERA ep  ?+lepton+X p Tmiss + lepton Neutral Current ep  eX p Tmiss X

62. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 5.When? Towards a CDR 5.When? Towards a CDR

63. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Timeline ● 2007: form working groups + steering committee initial meeting of conveners + committee SAC overview ● 2007/8: ECFA/CERN endorsement “work out” ● 2008: workshop I September 8+9 Divonne CH ● 2009: workshop II LHeC CDR [LHC Committee] ● 2011: LHeC TDR - construction 8 years ? - impact on LHC: civil engineering + installation e-ring and e-linac - be aware of CLIC progress

64. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 WG Structure ● accelerator (injector, ring or linac) Oliver Bruening (CERN) JBD (CI) ● interaction region (+ small angle detectors) tba ● infrastructure CERN + tba ● detector tba ● the new physics tba ● precision QCD and electroweak tba ● physics of high parton density tba

65. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 CDR Accelerator Design [RR and LR] Closer evaluation of technical realisation: injection, magnets, rf, power efficiency, cavities, ERL… What are the relative merits of LR and RR? Recommendation. Interaction Region and Forward Detectors Design of IR (LR and RR), integration of fwd detectors into beam line. Infrastructure Definition of infrastructure - for LR and RR. Detector Design A conceptual layout, including alternatives, and its performance [ep and eA]. New Physics at Large Scales Investigation of the discovery potential for new physics and its relation to the LHC and ILC/CLIC. Precision QCD and Electroweak Interaction Quark-gluon dynamics and precision electroweak measurements at the TERA scale. Physics at High Parton Densities [small x and eA] QCD and Unitarity, QGP and the relations to nuclear, pA/AA LHC and SHE physics.

66. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 LHeC Scientific Advisory Committee Experimentalists Joel Feltesse (Saclay/DESY) Roland Horisberger (PSI) Aharon Levy (Tel Aviv) Richard Milner (MIT) Allen Caldwell (MPI München) Chair John Dainton (Univ Liverpool) Accelerator Stephen Myers (CERN) Roland Garoby (CERN) Swapan Chattopadhyay (Cockcroft Inst) Ferdy Willeke (DESY/BNL) A Skrinsky (Budker) Theory Guido Altarelli (Roma) Stan Brodsky (SLAC) Lev Lipatov (Petersburg) John Ellis (CERN) Frank Wilczek (MIT) Labs Jos Engelen (CERN) Rolf Heuer (DESY) Young-Kee Kim (Fermilab) Peter Bond (BNL)

67. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Steering Group Oliver Bruening (CERN) John Dainton (Cockcroft) Albert DeRoeck (CERN) Stefano Forte (Milano) Max Klein - chair (Liverpool) Paul Newman (Birmingham) Emmanuelle Perez (CERN) Wesley Smith (Wisconsin) Bernd Surrow (MIT) Katsuo Tokushuku (KEK) Urs Wiedemann (CERN) setting up WGs + workshop I

68. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 4.Summary

69. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Now ● LHeC 70-140 e  7000 p GeV - can be built - has startlingly good luminosity ≥ 10 32 cm -2 s -1 grows with LHC pp luminosity - extends substantially, uniquely, and with synergy to LHC TeV discovery physics - probes chromodynamics @ new density frontier in uniquely comprehensive manner ep eA with unchallengable precision synergetically with LHC pp pA AA 10 34

70. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Proposal to ECFA As an add-on to the LHC, the LHeC delivers in excess of 1 TeV to the electron-quark cms system. It accesses high parton densities ‘beyond’ what is expected to be the unitarity limit. Its physics is thus fundamental and deserves to be further worked out, also with respect to the findings at the LHC and the final results both from the Tevatron and from HERA. First considerations of a ring-ring and a linac-ring accelerator layout lead to an unprecedented combination of energy and luminosity for lepton-hadron physics, exploiting the latest developments in accelerator and detector technology. It is thus proposed to hold two workshops (2008 and 2009), under the auspices of ECFA and CERN, with the goal of having a Conceptual Design Report on the accelerator, the experiment and the physics. A Technical Design report will then follow if appropriate. Endorsed by ECFA November 30 th 2007 Endorsed by ECFA November 30 th 2007

71. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 LHeC and ILC/CLIC ● energy for TeV eq discovery extreme chromodynamics ● precision for TeV eq discovery eq understanding extreme chromodynamics ●luminosity for TeV eq discovery LHeC and LHC Lepton + quark @ TeV LHeC RHIC FT LHC ●energy range for QCD phase equilibria

72. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Extras

73. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Lepton Ring ● in LEP tunnel … so like LEP - FODO in eight arcs β-tron phase advance φ H =108 o φ V =90 o - bending radius 3133.3 m - (δE/E beam ) rms = 1.1×10 -3 - SR 26 W/cm (E c =254 KeV) - scRF @ 1GHz resonators @ 12 MV/m 100 m structure = 670 cells  sync. phase 31 o  bucket takes 10× (δE/E beam ) rms - unlikely e-beam instability single bunch current modest impedance << LEP LEP=9 W/cm HERA=13.5 W/cm scRF proven @ > 6 MV/m 1 2 3 4 5 6 78

74. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Interaction Region ● highest lumi - low β e close sc quads - low X-ing angle “hard” bend 8σ beam sep n SR fan  sc p-beam « HERA - “crab” RF cavity p-bunch rotation 3.5 mrad 0.5 mrad V-displaced top elevation 11.4 kW 3.4 kW3.2 kW ● 1 o beam access = low-lumi/low-x option (cf HERA) “crabbed” (rotated) p-bunch

75. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 ● beam-beam - “hour-glass” - dynamic β: < HERA - long range beam-beam (parasitic interactions): marginal Operational Luminosity operational luminosity

76. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Barber Polarisation @ LHeC

77. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 What’s been achieved ● Sokolov-Ternov + spin-rotators @ HERA

78. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 What’s been achieved a)

79. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 LHeC ● tunnel exists (LEP, LHC) ● injection once existed (LEP) ? ● operating p-beam (from 2008) ● operating A-beam (from 2008) ● ep eA operating alongside pp pA AA ● the TeV ep collider ! ● ”minimal” mods to LHC ! ● LHC upgrade ● cost ?

80. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008

81. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 What’s been achieved ● Sokolov-Ternov @ LEP 70 GeV b)

82. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Diffraction and Rapgap rapgap η max η proton P + RII HERA  LHeC ~ 3 ● rapgap @ LHeC ?

83. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008

84. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Acceptance and Measurement e ! ● 70  7000 GeV ● high lumi quads (±10 o bp)  Q 2 > 100 GeV 2 x > 3×10 -5 ● few GeV ≤ E h,e ≤ few TeV ● low lumi for low x (no quads)  1 < Q 2 < 100 GeV 2 x < 3×10 -5  “forward” hadrons: “forward rapgap” instrumentation  precision e/had-measurement 170 < θ e < 179 o 170 < θ h < 179 o jet e

85. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Rate ● 100/10 fb -1 = 100/LHeC y @ Q 2 = 1 TeV 2 ● 100/10 fb -1 = 100/3×LHeC y

86. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Needle in a haystack… Higgs production QCD jet production at high energy Need to use signatures with small backgrounds: - Leptons - High-mass resonances - Heavy quarks to avoid being overwhelmed Need to use signatures with small backgrounds: - Leptons - High-mass resonances - Heavy quarks to avoid being overwhelmed

87. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008

88. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Producing a Higgs Higgs couplings  mass u-ubar  H has very small cross-section Dominant production via vertices coupling Higgs to heavy quarks or W/Z bosons Higgs couplings  mass u-ubar  H has very small cross-section Dominant production via vertices coupling Higgs to heavy quarks or W/Z bosons

89. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 Decay of the SM Higgs Width becomes large as WW mode opens Branching ratios change rapidly as new channels become kinematically accessible

90. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 a)  == forward elastic = diffraction = pomeron b)  == forward elastic = diffraction = pomeron W largeW W

91. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 c)  MXMX = X largeM X 

92. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 a) b)

93. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008  LHeC?

94. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 a) b)

95. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008

96. THE COCKCROFT INSTITUTE of ACCELERATOR SCIENCE and TECHNOLOGY Polarised Positron Workshop Meeting Cockcroft Institute March 28 th 2008 X xIxI P a)b)