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Summary of Tracking Devices For Huge Detector DESY SLAC CERN KEK - Vertexing - Tracking - Summary Jik Lee(SNU) for Hwanbae Park (KNU) Huge Detector Kickoff Meeting, Nov. 10 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Concepts of Huge Detector • Huge Detector: best optimized for “PFA” - excellent momentum resolution - good separation of clusters/tracks Solenoid Tracker SD TESLA Huge B(T) 5 4 3 Rin(m) 2.48 3.0 3.75 L(m) 5.8 9.2 8.4 Est(GJ) 1.4 2.3 1.2 Rmin (m) 0.2 0.36 0.40 Rmax(m) 1.25 1.62 2.05 σ(μm) 7 150 150 Nsample 5 200 220 dpt/pt2 3.9e-5 1.5e-4 1.1e-4 2004. 11. 10 Very Large Detector Kick-off Meeting maximize BL2 m SC-coil HCAL (Pb(Fe)/scinti or digital) W/Scinti ECAL TPC Si intermedi.-Trk SiVTX pixel(cold version) ▣ Vertexing Performance Requirements • excellent spacepoint precision < 4 microns • impact parameter resolution ≤ 5µm 10µm/(p sin3/2 ) • minimal multiple scattering 0.1 - 0.2% X0 or less per layer (transparency) • two track separation, occupancy 20 x 20 µm2 pixel size pixelated type • Charge Coupled Devices (CCD) • Monolithic Active Pixels (MAPs) • DEPleted Field Effect Transistor (DEPFET) • Silicon On Insulator (SOI) • Image Sensor with In-Situ Storage (ISIS) 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Beam Structures • Pileup over bunch train • Or fast timing warm • bx live: 3 10-5 power pulse • Fast readouts: OK, no pileup • Digital pipeline cold 2004. 11. 10 Very Large Detector Kick-off Meeting • bx live: 5 10-3 • readout speed • radiation hardness • occupancy ▣ Vertex Detector: CCD • faster readout needed for cold machine - need to readout every 50 µs (20 times) during a train ~0.5% occupancy - use Column-Parallel CCD with low noise (increase readout speed ~50MHz) CP CCD separate amplifier and readout for each column LCFI CP CCD 400x750 pixels(20µmx20µm) • cryostat for operation at 200 K - could be unnecessary with fast readout 2004. 11. 10 Very Large Detector Kick-off Meeting thin and mechanically stable ladder ▣ Image Sensor with In-situ Storage (ISIS) • 20 readouts/bunch train may be impossible due to beam –related RF pick up motivates delayed operation of detector for long bunch train: • charge collection to photogate from 20-30 µm silicon, as in a conventional CCD • signal charge shifted into storage register every 50 µs, providing required time slicing • string of signal charges is stored during bunch train in a buried channel, avoiding charge-voltage conversion • totally noise-free charge storage, ready for readout in 200 ms of calm conditions between trains 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Vertex Detector: MAPS Prototype ▪ standard CMOS sensor technology - readout/sensor on one chip - signal is corrected from epi. layer ▪ pixel size and precision ~ CCD • neutron irradiations - fluencies up to 1012 neutrons/cm2 are acceptable with considering LC requirements which is ~ 109 n/cm2/year • ionizing irradiations - tests up to a few 100kRad - exact sources of performance losses are under investigation (diode size and 5% drop in charge at 1.5e12 n/cm2 placements of the transistors are important parameters) 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Vertex Detector: DEPFET Prototype • thinning process for sensors established 800x104 mm2 for single pixel 2004. 11. 10 Very Large Detector Kick-off Meeting ▪ detector and amplification properties ▪ fully sensitivity over whole bulk ▪ very low noise operation at room temp. - sensitive area 50µm thinned - fast signal to cope with high rate requirement - resolution of 9.5 μm • complete clear no clear noise - (1 x clear) then sample 500x in 2.5ms - (clear + sample) 500x ▣ Vertex Detector Issue Pair background R(mm) B(T) (hit/mm2/train) • pair background hit at R=15mm is 1.7 times larger than that of 4T 15 • background hits are decreased significantly 15 at larger R 24 4 1.0 3 1.7 3 0.4 • configuration of R=20mm with silicon thickness < 70 µm satisfies the impact parameter resolution requirement: ≤ 5µm 10µm/(p sin3/2 ) • readout speed and rad. hardness • very thin detector Y. Sugimoto 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Tracking Performance Requirements • excellent momentum resolution - dilepton recoil mass for higgstrahlung process - end-point measurement for SUSY chains • excellent pattern recognition and 2 track resolution - high energy, high density jets • tolerant to high machine backgrounds -tracks in central tracker dominated by γγ events gaseous type (readout) • MWPC and pads - limited by positive ion feedback and MWPC response • MPGD’s (Micro Pattern Gas Detectors) - GEM (Gas Electron Multiplier) - MicroMEGAS (Micro Mesh GAS detector) 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ TPC with GEM • 50 µm Kapton foil for gas amplification • 5 µm copper coated on both sides • 70 µm holes, 140 µm pitch • hexagonally aligned holes • multiple GEM structures - safer operation - more flexibility to optimize charge transfer • GEM voltages up to 500 V yield 104 gas amplification 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ TPC with GEM • to reduce ion feedback -GEM with Micro Hole Strip Plate (MHSP) • apply negative strip voltage ions collected on strips, electrons extracted from holes due to diffusion IF is reduced by a factor of 4 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ TPC with MicromeGAS S1 • a micromesh sustained by 50-100 µm high insulating pillars • multiplication takes place btw anode and mesh S2 2004. 11. 10 Very Large Detector Kick-off Meeting • S1/S2 ~ Eamp/Edrift - can choose gap/HV to have gain maximum - ion feedback suppressed by Edrift/Eamp ▣ TPC with MicromeGAS • 50 cm drift, 1024 channels • tested up to 2T at Saclay - no gain drop with 55Fe Field cage pad layout: 1024 pads Readout Detector Berkeley-Orsay-Saclay TPC 2004. 11. 10 Very Large Detector Kick-off Meeting principle is proven but optimization to be done ▣ TPC Tracking Issue • small structures (no ExB effects) • fast electron signal • intrinsic ion feedback suppression • optimize novel gas amplification systems • ion feedback suppression • neutron backgrounds • optimize single point and double track resolution • demonstrate large system performance with control of systematics 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Intermediate and Forward Tracker • improve momentum resolution • improve track finding efficiency • forward tracking SET • intermediate between vertex and central (IMT, SIT, FTD) • intermediate between central and calorimeters (FCH, SET) • SIT + TPC + SOT 2004. 11. 10 Very Large Detector Kick-off Meeting • located btw vtx and main tracker (GLC model) - 5 layers at r=9 to 37 cm - angular coverage |cosΘ|<0.9 - spatial resolution σ = 20μm - total amount of Si required: 10 m2 ▣ Intermediate Tracker n+ implanted p-stop in atoll p+ implanted readout strip readout pad in staggering via in hourglass guard ring 64ch 50um pitch sensor 32ch 50um pitch sensor 16ch 50um pitch sensor 512ch 50um pitch sensor 1cm PIN Diode For SDD R&D Backside of SSD 2004. 11. 10 VeryN Large Detector side Kick-off Meeting PIN Diode array P side ▣ Tracking Devices • Si Vertex Detector 5 layers, t=70µm, =3µm cos < 1 (non-realistic) • Si Inner Tracker 3 layers (12, 24, 36 cm), t=300µm, =7 µm, cos<1 (non-realis tic) • TPC 40cm < R < 200cm, Z<235cm Ar gas, 220 samples, =150µm • Si Outer Tracker R=205cm(barrel)/Z=250cm(EC), =7µm Y. Sugimoto ΔPt/pt2 detail (realistic) simulation studies are underway 2004. 11. 10 Very Large Detector Kick-off Meeting Pt(GeV/c) ▣ Vertexing/Tracking Issues • R&D must be guided by continuing physics and simulation programs which can deliver the accuracy that the LC physics needs - evaluate the tracking performance: backgrounds, occupancy studies, pattern recognition studies • demonstrate performance in large scale prototypes in cosmic ray and test beams studies with the magnetic field • vertex detector, tracker, calorimeters should be integrated for optimal jet reconstruction 2004. 11. 10 Very Large Detector Kick-off Meeting 2004. 11. 10 Very Large Detector Kick-off Meeting ▣ Physics Performance • end-point measurement for SUSY chains GLC project report 2004. 11. 10 Very Large Detector Kick-off Meeting