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Detector Requirements for ILC Experiments. Akiya Miyamoto KEK. 6 April 2005. 素核研 研究計画委員会. Hitoshi Yamamoto, Jan. 2005. Detector Performance Goals. Vertexing, b,c tags ... 1/5 r beampipe ,1/30 pixel size wrt LHC : Tracking, tagged Higgs ... 1/6 material, 1/10 resolution wrt LHC :
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Detector RequirementsforILC Experiments Akiya Miyamoto KEK 6 April 2005 素核研 研究計画委員会
Hitoshi Yamamoto, Jan. 2005. Detector Performance Goals • Vertexing, b,c tags ... • 1/5 rbeampipe,1/30 pixel size wrt LHC : • Tracking, tagged Higgs ... • 1/6 material, 1/10 resolution wrt LHC : • Jet energy (quark recon.) W,Z separation... • 1/2 resolution wrt LHC :
Contents • Introduction to ILC experiments • Detector performance and physics • Jet energy measurement • Vertex detector • Tracker • Summary
5k events/4y Cross sections + New physics SM processes • Jets are copiously produced at ILC. Efficient detections of jets are crucial for physics involving W/Z/Top/H..
Key feature of ILC events • Many of our signals are jets. ~ ~ • Wgl n is not usable for angular analysis for processes with >2W, LSP, etc • Efficient detection of jet gains the statistics • Provides a way to study new physics in quark sector ( model independent study ) • thanks to cleaner environment of ILC • Increases power when combined with a vertex detector • b, c tag, and jet charge ID • W/Z mass difference is ~ 10 GeV g good detector system is crucial.
Detector for ILC experiments Detector design Philosophy • Good jet energy resolution g calorimeter inside a coil • highly segmented calorimeter • Efficient & High purity b/c tagging g Thin VTX, put close to the IP • Strong solenoid field • Pixel type • High momentum resolution • Hermetic down to O(10)mrad • Shielded enough against beam-related background Muon detector Calorimeter Coil Vertex detector Tracker
GLD tentative parameters Optimization of detector parameters are now in progress.
4-jet 2 lepton+X 2-jet+missing Examples of basic physics capability Decay mode independent Higgs search • Model independent study of Higgs Studied using old “GLC” detector parameters. Expecting basically similar performance for GLD – needs to be confirmed. Better performance meanes - smaller meas. error with same integrated Luminosity or - same meas. error with smaller integrated Luminosity
Error on Br(HgWW*) • 2nd largest Br, if Mh~120GeV • Combined with stotal(e+e-gZH), get GH(Total width of H) DBr/Br~4.8% DBr/Br~4.2% Based on TESLA detector
Mbb (GeV) Mbb (GeV) Mbb (GeV) Mbb (GeV) DMh in ZHg4jet DEj/Ej : 60% g 30% DMh improves ~16% In terms of Int. Lum. ~30% less Acc. operation. T.Barklow @LCWS2005
e+e-gnnWW/nnZZ • Main processes to study if Higgs sector is strongly interacting Distribution: Sum of BreitWigner and Gauss s of Gauss is a/sqrt(E) No. of Events=sxLxBr(W/Zgqq’) M2qq(GeV) M2qq(GeV) Projection to M1=M2 M1qq(GeV) M1qq(GeV) Hard to separate W/Z
SUSY study in jet mode SUSY parameter: m0=500GeV, m=400GeV M2=250GeV, tanb=3 M2qq(GeV) M2qq(GeV) M1qq(GeV) M1qq(GeV) Hard to find Neurtalino
e+e-g ZHH at 500 GeV By Yasui • Main channel to study Higgs self-coupling • Total cross section ~ 0.2fb @ 500 GeV • Analysis by TESLA • DIST is used to separate signal from background • Jet energy resolution is crucial to see signal
ILC Calorimeter Jets in ILC detectors LEP ex. : ALEPH GLD Dots are signal ! Zoom
A Full Simulation Study Example performance: TESLA TDR e+e- g Z • Analysis is based on Geant3 based TESLA detector simulator and reconstruction tools used for LEP studies. • 30%/sqrt(E) is achievable • Remaining studies • Improvements towards < 30%/sqrt(E) • Other processes • Other configuration: GLD/LDC/SiD • Better simulation tools : Geant4 based
SNARK (DESY) Tube along track g transverse profile to further collect hits gNeutral clustering (SNARK) from LDC meeting @Paris, Jan, 2005
PFA Development Status – True vs Current PFA ANL/SLAC (Steve Magill) SiD Track-Cell Associationg Photon finder g Neutral Clustering • True PFA (no confusion) • -> 28%/E e+e-g Z g 2-jet Two component in reconstructed Invairant mass. Newutral Reconstruction is dificult Current PFA Status 35%/E (conical showers) 70%/E (needs work!*) * Improved with better neutral reconstruction
Mz resolution by Jupiter(GLD) • Geant4 based simulation • Perfect PFA. Reconstruction code is yet to be developed. • Gap between naïve expectation and Geant4 simulation needs to be studied. e+e-g Z at 91GeV Preliminary result by Sumie Yamamoto
Vertex detector : Eff., Purity • Goal of ILC Vertex detector Less light quark bkg. such as Hgcc c.f. SLD VXD3 • High performance allows usnot only b-tag, but also • C-tag • Vertex charge ID e+e-g Z0 case TESLA TDR
Vertex detector : Challenge • But, • ILC bunch structure: ~330 ns spacing, ~3000 bunch, 5Hz pulse • Background : ~3hits in 100mmx100mm /pulse • We need to • store signal near pixel during the pulse, • or use very small pixel. • To achieve VTX performance goal, • Put VTX close to IP • Thin(~0.1%R.L./layer) structure • Increase # of layers : 3 g 5~6 No proven technology satisfies these requirements
Physics with Vertex detector • High performance Vertex Detector allows us not only to tag b-bbar, but also • c-cbar tag • Jet charge ID • These capabilities are very useful measure • Higgs : Branching ratio to b-bbar, c-cbar • Efficient and clean ID of b/c will help to reduce • combinatorial backgrounds in multi-jet events: e+e- g tt, ttH, H+H-, … • Backgrounds from other jet events: e+e- gnnhh, … • Polarization analysis of top: t g bW+, W+g c sbar: Probe of BSM • Coupling asymmetries of Z0: Ab(0.94), Ac(0.67) cf. Al=0.15 • Effects of large ED to e+e- g bb/cc is stronger than e+e- g ll channel. • Charge IDs of jets from chargino/neutralino decay are indispensable foranalysis of angular correlations
Sabine Riemann: one example for large ED, sqrt(s) = 0.5 TeV For these channels, sensitivity extends to MD around 5 TeV For muon pairs, effects are much weaker (not measurable even with 1 ab-1 of data) from C.Damarell, LCWS2005
Vertex tagging ex. • To achieve high efficient and high purity b/c tagging, good vertex detector is crucial Old results by G.B.Yu for Hgc cbar meas., using MSTPM alone Good VTX saves ~40% of running time!
Higgs study in lepton mode • Higgs mass measurement by Z recoil method • Model independent Higgs search • Dmh~50MeV, Ds/s~3% possible in SM • Mh is very sensitive to loop effect in SUSY models: • Lesser effects of beam related background • Needs excellent tracker performance
H gm+m- • Br(H gm+m-)~0.023% if MH=120GeV g ~50 events produced at 250GeV,1ab-1 • Physics motivation: Yukawa coupling of 2nd generation • Consider e +e -g ZH g jets + m+m-, • Simple S/N estimate by Breit Wigner + Gaussian • Breit Wigner shape is expected background from e+e-g ZZ Our target ALEPH 1ab-1 @ 250 GeV Dp/p2=5x10-5 M(m+m-) (GeV) • 100% eff. assumed. • Realistic simulation required
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Summary • There are several processes which requires ultimate detector performances. • In other processes, high performance gains statistics or precisions of measurements. Equivalent to increase ILC luminosity • Topicsnot convered • Forward tracker/calorimeter • Crucial for Luminosity meas. and dark matter search. • More quantitative and systematic study g Study items towards Detector Outline document to be completed by Spring 2006. • “State of art” detector technology is a key to realize detector performance.