A part of Examples of Physics research covered by ILC

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2 A part of Examples of Physics research covered by ILC 1 st stage: Ecm = GeV, Luminosity = ~ / fb / year x several years. 2 nd stage: Ecm = 1 TeV Nov S. Yamashita, 7th ACFA WS 2

3 Goals of ILC 1. Unexpected new signals 2. Electroweak symmetry breaking and massgeneration 3. Direct signals for new physics (SUSY, extradimensions, Z ) and determine The Physics 4. GUT and Planck scale physics Nov S. Yamashita, 7th ACFA WS 3

4 LHC Signal and background Cross-section σ(fb) ILC Number of events / 500 fb -1 Nov S. Yamashita, 7th ACFA WS 6

5 Powerful Tools at ILC Electron/positron collision (elementary process) High Energy and High Luminosity Energy scan (controllable) Controllable beam polarization Very sensitive detectors & Trigger free Precise theoretical calculation (<1%) Precise physics information & long energy reach LHC gives us a new global (mixed) picture. ILC gives us new dynamic multi-dimensional total views. Nov S. Yamashita, 7th ACFA WS 5

6 Precision gives us a lot! Nov S. Yamashita, 7th ACFA WS 16

7 LHC Higgs signal H γγ ILC Higgs signal Bkg. tth WbWbbb lνjjbbbb ATLAS 30fb -1 Bkg. ILC e+e- HZ production Typical numbers Tagging efficiency ~ % S/N > 1 Nov S. Yamashita, 7th ACFA WS 21

8 Performance Goal of ILC Detectors VT Impact Parameter resolution: < 5µm + 10µm / p(gev) sin -3/2 θ Tracker Momentum resolution: dp/p < 5 x 10-5 x p(gev) (central region) 3 x 10-4 x p(gev) for forward region Angular resolution: dθ < 2 x 10-5 rad (for cosθ <0.99) Jet energy resolution: de/e < 0.3 / E(GeV) Excellent Hermeticity: down to θ < mrad (active mask) Nov S. Yamashita, 7th ACFA WS 8

9 Challenge In order to accomplish our physics goal at ILC With respect to detectors at LHC: Inner VT layer 3--6 times closer to IP VT pixel size 1 / 30 VT materials 1 / 30 Materials in Tracker 1 / 6 Track mom. resolution 1 / 10 EM cal granularity 1 / 200!! Nov S. Yamashita, 7th ACFA WS 9

10 Coupling Precision LHC 300 fb -1 x 2 Deviation from SM value +30% +20% +10% 0%(SM) -10% -20% Γ h τ b t W Z Model assumption -30% Nov S. Yamashita, 7th ACFA WS 26

11 Coupling Precision ILC Deviation from SM value Γ h +30% c τ b t W Z H +20% +10% 0%(SM) -10% -20% Model Independent Analyses -30% Nov S. Yamashita, 7th ACFA WS 27

12 SUSY or 2HDM ILC Deviation from SM value Γ h +30% c τ b t W Z H +20% cosα/sinβ +10% 0%(SM) -10% sin(α β) -20% sinα/cosβ Model Independent Analyses -30% Nov S. Yamashita, 7th ACFA WS 28

13 Collider Constraints Linear Collider Detector R&D has had to consider two different sets of collider constraints: -Band RF and Superconducting RF designs #bunch/train #train/sec -Band GLC/NLC /120 SuperRF TESLA With the linear collider technology selection, the detector efforts can concentrate on one set of parameters The ILC creates requirements similar to those of the TESLA design bunch spacing bunches/sec length of train train spacing crossing angle 1.4 nsec 28800/ nsec 6.6/8.3 msec 7-20 mrad 337 nsec µsec 199 msec 0-20 mrad J. Brau - ACFA Workshop, Taipei - Critical Questions November 9,

14 Detector Concept Studies Time to re-evaluate detector concepts based on : up-to-date detector R&D results refined physics benchmarks some design need to be re-thought for the cold machine (longer bunch train etc.) Detector concept session during this workshop (this afternoon) Concept 1 : silicon-tracker-based (SiD) Concept 2 : medium Tesla-based Concept 3 : large GLC-based (GLD) H. Yamamoto, ACFA07

15 LC Detector Requirements Any design must be guided by these goals: a) Two-jet mass resolution comparable to the natural widths of W and Z for an unambiguous identification of the final states. b) Excellent flavor-tagging efficiency and purity (for both b- and c- quarks, and hopefully also for s-quarks). c) Momentum resolution capable of reconstructing the recoil-mass to di-muons in Higgs-strahlung with resolution better than beamenergy spread. d) Hermeticity (both crack-less and coverage to very forward angles) to precisely determine the missing momentum. e) Timing resolution capable of separating bunch-crossings to suppress overlapping of events. J. Brau - ACFA Workshop, Taipei - Critical Questions November 9,

16 A Medium Size Detector for the ILC... what used to be the TESLA or LD detector concept Ties Behnke: A medium size LC detector Ties Behnke, DESY on behalf of the European and American large detector concept groups 1 A medium size detector for the linear collider: The concept behind the TESLA/ LD detector precision tracking particle flow based event reconstruction Ways to proceed: global detector optimization

17 A Precision Tracker Ansatz from the TESLA TDR: Ties Behnke: A medium size LC detector (see e.g. Paolo Checcia's talk at LCWS04) 4 large volume gaseous tracker medium precision SI tracker to join the two devices high precision VT forward SI tracking for low angles forward tracking behind TPC endplate

18 Why a TPC? Ties Behnke: A medium size LC detector advantages of a gaseous detector: 7 many space points (200 for current design) good precision TPC is true 3D device: very robust against backgrounds long lived particles (new particles) Thin (little material) disadvantage: gas amplification structures needed HV needed (REAL HV in case of a TPC) fairly massive endplates seem unavoidable readout speed is limited by gas properties

19 Gaseous Tracking Ties Behnke: A medium size LC detector e e H 0 A 0 b b b b 6 advantages of gaseous tracking: many points simple pattern recognition redundancy but be careful with these comparisons! Much more detailed studies are needed!

20 Event Reconstruction Jet physics: event reconstruction need excellent jet-energy (= parton energy) reconstruction Ties Behnke: A medium size LC detector WW-ZZ separation 12 Complex hadronic final states: need complete topological event reconstruction Needed: new approach which stresses event reconstruction over individual particles: Higgs self coupling reconstruction Particle flow More like a revolution (though many have tried this before...)

21 Particle Flow: Basics Jet = 2 T E 4 i 2 ECAL E i 2 HCAL E / E σ(e)/e tracker HCAL 120 GeV ECAL practical limit E / E =0.3 / sqrt GeV E(GeV) HCAL ECAL tracker resolution scale 13 Ei 370 GeV for perfect separation Ties Behnke: A medium size LC detector Resolution is dominated by HCAL and by confusion resolution Resolution tracker - Calorimeter Effect of changing the resolutions by a scale factor jet energy resolution is nearly independent from tracker res. driven by HCAL res ASSUMING: perfect separation of particles

22 Size Matters Ties Behnke: A medium size LC detector Study confusion between charged and neutral particles as function of radius: 15 e+e -> ZH -> jets at s = 500 GeV 127 cm 168 cm physics and CMS energy drive the relevant length scale d (cm) Jean Claude Brient Energy deposited within d cm around a charged track numbers: E=20 GeV photon energy within 2.5cm of track for R=168 cm (4T, SiW) E=65 GeV photon energy within 2.5cm of track for R=127 cm (5T, SiW)

23 Particle Flow Detector Particle Flow is influencing the detector design: Ties Behnke: A medium size LC detector Large inner radius of ECAL to have good separation at moderate fields 14 Both ECAL and HCAL inside the coil Excellent spatial resolution of ECAL and HCAL to maximize the shower tracking ECAL: obvious choice is Tungsten absorber, fine grained readout (SI seems accepted technology) HCAL: less obvious, different options are under study (analogue, digital... ) But all push the granularity ( = number of channels = cost) to new limits Try to really optimize the size and granularity requirements to optimize the cost

24 Calorimeter Concepts Ties Behnke: A medium size LC detector The medium detector concepts: SI-W ECAL calorimeter excellent granularity excellent coverage dense 16 followed by dense and segmented HCAL scintillator tile digital option ECAL module cm LAYERS! Alveoli Tungsten Carbon fiber more conventional solution studied: compensating lead-scintillator calorimeter hybrid solutions (SI layers in conventional) Detector slab My personal opinion: we want the first, but maybe can only afford the second solution: need to wait for R&D program results!

25 Status of Detector Concept Current invariants of the concept: Tracking based on TPC plus Silicon Tracker Ties Behnke: A medium size LC detector Fine grained ECAL and HCAL to optimize particle flow 18 aggressive coverage to very small polar angles The rest of the parameter space is wide open: Need to start a real optimization Need to fold in the results from the detector R&D which will be coming in during the next few years

26 SiD design study SiD starting point (1) H.Weerts Starting point: SiD concept Accept notion that excellent energy flow calorimetry is required, and explore optimization of a TungstenSilicon EMCal and the implications for the detector architecture ECFA 04, Durham, Sept. 04

27 Calorimetry drives the Detector Design W s, Z s, top, H s, are the quanta we must identify, and missing energy is the critical signature. All depend on calorimetry. Need to measure jet four-momenta well enough to identify and discrimminate W s, Z s, top, H s, Need ~4π acceptance for good efficiency with multi-jet final states SiD starting assumptions particle flow calorimetry will deliver the best possible performance Si/W is the right technology for the ECAL Taipei ACFA Jaros 2

28 SiD design study SiD concept sizes H.Weerts Overall SiD Size of VD outer cryostat and EMCAL (EMCAL inner radius larger than Dzero EM cal radius) ECFA 04, Durham, Sept. 04

29 The SiD Rationale Premises: Excellent physics performance, constrained costs Si/W calorimetry for excellent jet resolution therefore Limit Si/W calorimeter radius and length, to constrain cost Boost the B field to recover BR 2 for particle flow, improve momentum resolution for tracker, reduce backgrounds for VD Use Si microstrips for precise tracking Taipei ACFA Jaros 3

30 Cost (and physics) balance R and B High Field Solenoid and Si/W Ecal are major cost drivers Magnet Costs Stored Energy (SiD ~1.1GJ M$) Cost [M$] Fix BR 2 =7.8, tradeoff B and R Cost Partial, Fixed BR^ Linear Power Exp Data Stored Energy [GJ] Delta M$ Linear Power Radius B Delta M$ vs B, BR 2 =7.8 [Tm 2 ] Taipei ACFA Jaros 4

31 Result: SiD Design Starting Point B = 5T R ecal = 1.25m Z ecal = 1.74m Taipei ACFA Jaros 5

32 ECAL Taipei ACFA Jaros 7

33 HCAL Inside the coil R in = 1.42m; R out = 2.44m 4λ Fe (or W, more compact) 2cm Fe, 1cm gap Highly segmented 1x1 cm 2 3x3 cm 2 ~ 40 samples in depth Technology? RPC Scint Tile GEM S. Magill (ANL) many critical questions for the SiD Design Study: thickness? Segmentation? Material? Technology? Taipei ACFA Jaros 9

34 Basic design concept Performance goal (common to all det. concepts) Vertex Detector: Tracking: δ ( IP) 5 10 / δp Jet energy res.: δe / E 0.3/ E Detector optimized for Particle Flow Algorithm (PFA) Large/Huge detector concept GLC detector as a starting point Move inner surface of ECAL outwards to optimize for PFA Larger tracker to improve δp t /p t 2 t / p 2 t 5 10 psin Re-consider the optimum sub-detector technologies based on the recent progresses 5 3/ 2 θ

35 Optimization for PFA Jet energy resolution σ jet2 = σ ch2 + σ γ2 + σ nh2 + σ confusion 2 + σ threashold 2 Perfect particle separation: Charged-γ/nh separation σ jet / E ~ 15% / Confusion of γ/nh shower with charged particles is the source of σ confusion Separation between charged particle and γ/nh shower is important Charged particles should be spread out by B field Lateral size of EM shower of γ should be as small as possible ( ~ R effective m : effective Moliere length) Tracking capability for shower particles in HCAL is a very attractive option Digital HCAL E

36 Optimization for PFA Figure of merit (ECAL): Barrel: B R in2 / R m effective Endcap: B Z 2 / R m effective R in : Inner radius of Barrel ECAL Z : Z of EC ECAL front face (Actually, it is not so simple. Even with B=0, photon energy inside a certain distance from a charged track scales as ~R in2 ) Different approaches B R in 2 : SiD B R in 2 : TESLA B R in 2 : Large/Huge Detector R d=0.15br 2 /p t

37 Central Tracker Figure of merit: δp t ( 3.3 ) 720 = σ 2 2 p BL n + 4 t σ :Spatial resolution B : Magnetic field L : Tracking length n: Number of samplings n is proportional to L if sampling pitch is constant δp t pt BL 1

38 A possible modification from GLC detector model Larger R max (2.0m) of the tracker and R in (2.1m) of ECAL TPC would be a natural solution for such a large tracker Keep solenoid radius same: Somewhat thinner CAL (but still 6λ), but does it matter? Use W instead of Pb for ECAL absorber Effective R m : 25.5mm 16.2mm (2.5mm W / 2.0mm Gap) Small segmentation by Si pad layers or scintillator-strip layers Put EC CAL at larger Z (2.05m 2.8m) Longer Solenoid Preferable for B-field uniformity if TPC is used It is preferable Z pole-tip < l* (4.3m?) both for neutron b.g. and QC support (l* :distance between IP and QC1)

39 Global geometry 700 (All parameters are tentative) Main Tracker EM Calorimeter H Calorimeter Cryostat Iron Yoke / Muon System QC1 S

40 Comparison of parameters SiD TESLA JLC GLC GLD [1] LD Solenoid B(T) Rin(m) L(m) E st (GJ) Main Tracker R min (m) R max (m) BL 2.5 σ(µm) N sample δpt/pt e e e e-4 [1] GLD is a tentative name of the Large/Huge detector model. All parameters are tentative e e-4

41 Comparison of parameters ECAL E+H CAL R in (m) BR in 2 SiD TESLA Type W/Si W/Si R eff m (mm) BR in2 /R eff m Z (m) JLC GLC Pb/Sci Pb/Sci (W/Sci) Pb/Sci BZ 2 /R eff m λ t (m) GLD LD

42 Detector size EM Calorimeter SD: 1.27m TESLA: 1.68m GLD: 2.1m Area of EM CAL (Barrel + Endcap) SiD: ~40 m 2 / layer TESLA: ~80 m 2 / layer GLD: ~ 100 m 2 / layer (JLC: ~130 m 2 / layer)

43 Global geometry SD TESLA GLD 5 m Main Tracker EM Calorimeter H Calorimeter Cryostat Iron Yoke / Muon System

44 Global geometry CMS GLD Main Tracker EM Calorimeter H Calorimeter Cryostat Iron Yoke / Muon System 5 m GLD is smaller than CMS Large is smaller than Compact

45 Merits and demerits of Large/Huge detector Merits Advantage for PFA Better p t and de/dx resolution for the main tracker Higher efficiency for long lived neutral particles (Ks, Λ, and unknown new particles) Demerits Cost? but it can be recovered by Lower B field of 3T (Less stored energy) Inexpensive option for ECAL (e.g. scintillator) Vertex resolution for low momentum particles Lower B requires larger R min of VT because of beam background δ(ip)~5 10/(pβsin 3/2 θ) µm is still achievable using wafers of ~50µm thick

46 Full Simulator Installation of a new geometry into a full simulator JUPITER is under way

47 Charged γ separation Simulation by A. Miyamoto Events are generated by Pythia6.2, simulated by Quick Simulator Particle positions at the entrance of EM-CAL Advantage of Large/Huge detector is confirmed Inconsistent with J.C.B s result need more investigation F F all events E ( d < d ) γ all events E γ cut d cut

48 Kick-off Detector R&D efforts & Design Studies H.Weerts Vxd 4-5 SiLC T P C J e t Calic e EM Calic e HAD LC cal Cal Asia EM OR/ SLAC EM hybrid mu on SiD LAD HUD? SiD Fwd trac Fwd cal Fwd Che DA Q γγ BD IR Nearly all detector R&D efforts are represented in the Design Studies (DS) LAD HUD?? Goal: At least one representative of each R&D effort in each DS ACFA-7; Taipei, Nov 2004

49 Timeline proposed by WWS OC (2004) ITRP tech. recommendation (2005) Accelerator CDR (2007) Accelerator TDR Set up 3 panels (costing, detector R&D, and MDI) Single preliminary-costing paper for >1 whole detector concepts WWS receives CDR from each detector concept team (2008) LC site selection Site selection + 1yr Collaborations form and submit LOIs for proposal to the global lab (or GDO?) Global lab selects experiments. H. Yamamoto, ACFA07