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e-e-, gamma-gamma and e-gamma options for a Linear Collider. De Roeck CERN. Amsterdam, April 2003. In this study. Gamma-gamma and e-gamma option Working group on gamma-gamma/e-gamma collider technology K. Moenig and V. Telnov Working group on gamma-gamma physics
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e-e-, gamma-gamma and e-gamma options for a Linear Collider De Roeck CERN Amsterdam, April 2003
In this study • Gamma-gamma and e-gamma option • Working group on gamma-gamma/e-gamma collider technology K. Moenig and V. Telnov • Working group on gamma-gamma physics M. Kraemer, M. Krawczyk, S. Maxfield, ADR, (S. Soldner- Rembold) • 4+2 meetings during this study • During ECFA/DESY, integrated with other physics groups/ worked well! • Many new results • e-e- option • No new studies in the context of this workshop/ 2 meetings St Malo/Amsterdam C. Heusch • Will remind some key issues based on Snowmass/Jeju reports
e-e-option Advantages of e-e-: Large polarization for both beams: eL,eR Exotic quantum numbers (H--) Larger sensitivity in some processes Some very clean processes No s-channel, lower luminosity Sensitivity to contact interactions Non-Commutative QED …Majorana neutrinos
e-e- option Higgs production Supersymmetry CP viol. phases But: No detector simulation, IR, beamstrahlung, selectron width…
e-e- option Parameters (Snowmass 2001) Study for TESLA (S. Schreiber) Luminosity 5-(10)•1033 cm-2 s-1 L e-e- = 1/6 –(1/3) L e+e- Stability ~OK with intra-train feedback system
e-e- option S. Schreiber No major changes required in IP or accelerator e-e- is the option which will be most easily to realize (for TESLA) Has to be kept on the roadmap Future control room at the FLC??
Gamma-gamma and e-gamma • Compton backscattering on laser photons • Needs second interaction point • Needs crossing angle • Peaked but smeared spectrum • Hence: needs extra effort • Is it worthwile? • Jeju panel discusion: Yes! • Examples of advantages • Higher cross sections for charg. particles • Different JPC state than in e+e- • Higgs s-channel produced • Higher mass reach in some scenarios • CP analysis opportunities • Can test precisely couplings to photons…
Gamma-gamma and e-gamma • TESLA-TDR/ PLC workshop Hamburg 2000 Golden processes identified Starting point in Krakow Only light Higgsbb and QCD processes simulated (simplified) • This study: Level of detail in as good as in e+e- • SIMDET simulation for more golden processes • H WW, ZZ , Heavy MSSM H & A, WW production, Susy • Cross checks/elaborate for key process Higgs bb • Further opportunities: CP studies, Extra Dimensions, NC QED,.. • Real luminosity spectra/polarization used (CIRCE, CompAZ) • B search using ZVTOP • Adding overlap events • QCD backgrounds in NLO • QCD Monte Carlo tuning to existing data • Direct contact & exchange with the US studies/exchange tools
Gamma-gamma and e-gamma • Backgrounds and Luminosity • Luminosity/polarisation measurement (& corresponding syst.) • Background studies (pairs, photons, neutrons) • Evaluate design of IP/Mask/vertex detectors • Technology • R&D efforts in Europe and the US
Golden Processes hep-ph/0103090 • NO W TDR Higgs SUSY Tril/quart. Top QCD • Being done or ready: should be ready for the writeup • promised
Golden Processes Added at/since the Krakow meeting: Non-commutative QED e for ED’s Light gravitinos Radions Gluino production H (US groups) HH+H- (US groups) CP analyses in the Higgs sector More (as yet uncovered/lower priority at present) ee* Leptoquarks Strong WW scattering eeH As always: still room for volunteers (next workshop)
Gamma-gamma and e-gamma On our group web page… Information on lumi spectra, special SIMDET version, background…
Luminosity Spectra TDR parameters Luminosities files with PHOCOL (V. Telnov) Can be used via CIRCE (T. Ohl) Analytical approximation COMPAZ (A. Zarnecki)
Luminosity Measurement • Proposals • ee ee () / not for J=0 • ee ee () • ee 4 leptons • Precision ~0.1% (stat) • For Higgs (J=0) e.g. ee ee Moenig,Marfin,Telnov • Fore collisions • e e • e eee
Monte Carlos & Tuning • Amegic & Wing SHERPA Generator (F. Kraus et al.) Tuning of the Monte Carlo models via JETWEB (M. Wing) Resolved Direct A tune for LC studies has been produced
Background studies backgrounds studied for TESLA IP layout Study beam related background # of QCD events overlapping now under control ( 1 evt@ 200 GeV and 2.5 evts @500 GeV). All groups agree (D. Asner, ADR, Telnov, Warsaw) # of hits in the layers of the pixel detector per bunch crossing Incoherent pair production: essentially the same as for e+e- Coherent pair production: High! but ok, similar to e+e- same vertex detector as for e+e- (Moenig,Sekaric) Neutrons? Probably ok (V. Telnov) Moenig et al 1st layer 2nd layer…
QCD QCD had been mostly studied --at detector level-- for the TDR Not revisited this time • Exceptions (using new data) • Total cross section parametrizations (Kwiecinski, Motyka,Timneanu) & (Pancheri, Grau, Godbole, ADR) • Structure functions PDFs (Krawczyk et al.) To be used in the Monte Carlo programs
Higgs • From the TDR(Jikia, Soldner-Rembold) • This workshop • Study H bb, with realistic spectra, background, B-tagging efficiency,… • Study H WW,ZZ • Study model separation power • Study spin of Higgs in H WW,ZZ • Study CP properties of the Higgs • Study MSSM Higgs (H,A): extend e+e- reach • Study of the Charged Higgs (US) Heralded as THE key measurement for the gamma-gamma option 10 3 250 350
SM Higgs analyses P. Niezurawski 1 year/84 fb-1 Corrected inv. mass Using NLO backgrounds (Jikia…) Next question:Systematics…??
SM Higgs Analysis • Analysis of a second group (Zeuthen) • Taking into account the QCD radiative corrections to the background process (Pythia + NLO Xsec.) through a reweighting procedure. • Adopting a b-quark tagging algorithm based on a neural network. A. Rosca = 1.9%
SM Higgs: HWW,ZZ A. Zarnecki Simultaneous determination of the Higgs Boson width and phase H WW and H ZZ measurements (full detector simulation) / = 3-10% MH< 350 GeV
SM Higgs Analysis Warsaw group 2HDM SM-like versus SM (Ginzburg et al.) Different masses MHbb (GeV) /
MSSM H/A Higgs One year running and s 500 GeV A0 detectable for MA > 300 GeV beyond the e+e- reach Extend the detailed analysis to H/A bb P. Niezurawski
MSSM H/A Higgs Study for a e+e- collider at 630 GeV e+e- • D.Asner/J.Gunion (LCWS02) • Extends e+e- reach • Need few years to close the LHC wedge • European study in progress
Angular distributions in hZZlljj and hWW4j Higgs spin and parity A. Zarnecki D. Miller et al. hep-ph/0210077 Detector effects are large, but sensitivity left
CP studies via tt R. Godbole et al. hep-ph/021136 & LCWS02 Exciting possibility to analyse CP structure of the scalar Construct combined asymmetries from intial lepton polarization and decay lepton charge Done with Compton spectra Using COMPAZ reduces sensitivity with factor 2 Needs detector simulation
Triple Gauge Couplings Study WW eW Sekaric, Moenig Bosovic, Anipko Includes detector simulation/3D fits sensitivity~ proportional to the momentum of the particles involved in the triple gauge boson vertex Studies starting for quartic couplings in WW and WWZ I Marfin Use of optimal variables F. Nagel et al.
Extra Dimensions ADD type extra dimensions Sensitivity to mass Ms P. Poulose tt Realism reduces sensitivity: Ms=1.7 TeV to 1.4 TeV =-1 see= 500 GeV SM+2 SM-2 =+1 Ms Ms Ideal Compton spectrum COMPAZ spectrum
Supersymmetry Theoretical studies: gluinos Interesting but needs simulation Several analyses starting charginos squarks eslepton neutralino Will be pursued up to the detector level E.g. Kraus, Wengler Klasen, Berge
Technology • Photon collider IP introduces new challenges • Laser • Optics • Stability & control in the IP (1nm?) /length control in cavity • Extraction line… • Both Europe & US groups have and R&D effort. • Europe: use a cavity to reduce laser power • US: full power laser design • US: laser commissioning 20 J pulses at 10 Hz / Full power next year • interferometery for alignment • ½ size focusing optics setup in lab • beam-beam deflection feedback system study • PC testbed at SLAC? Proposal under preparation • Europe : study cavitiy option • Make 1:9 size test cavity? Wait for funding/technology decision? Funding is an issue to continue R&D!
Interferometric Alignment System Testbed at LLNL • Half-scale prototype of optics / alignment system to test mirror quality and alignment scheme • Optics and laser interferometer currently installed J. Gronberg
gg Engineering Test Facility at SLCRevive SLC and install beampipe with opticsto produce gg luminosity 30 GeV 1100 / 50 1600 / 160 8 / 0.1 mm 0.1 – 1.0 mm 1500/55nm 6.0E9 Beam Energy DR gx,y (m-rad) FF gx,y (m-rad) x / y z x,y N
G. Klemz New proposal
Conclusions • Lot of activity on gamma-gamma during this workshop series • Good balance found between gamma-gamma specific meetings and integration with the other groups • Good progress on tools/background etc, for gamma-gamma studies • Many detailed studies • The light Higgs results confirmed and extended / ~ 2% • Higgs channels in WW,ZZ studied / ~ 3-10% • H/A study confirms reach for high masses, beyond e+e- • CP, Higgs spin etc studies starting • Detailed study of the TGCs measurement competitive with e+e- • First results on SUSY and Extra Dimensions/alternatives explore during the continuation of the workshop Confirms /e as an exciting option for a LC ! • Progress also with hardware plans (PC testbed/Berlin studies) Big thanks to all participants, particularly the Warsaw and Zeuthen Groups