Latest Results of the ILC Large TPC Prototype (LPTPC) G. De - PowerPoint PPT Presentation

Latest Results of the ILC Large TPC Prototype (LPTPC) G. De Lentdecker Université Libre de Bruxelles Brussels, Belgium On behalf of the LCTPC Collaboration

Overview • Introduction • Motivations, experiment and collider concepts • TPC • Micro Pattern Gaseous Detectors (MPGD) • The Large Prototype TPC (LPTPC) • Beam test setup in DESY • 3 detector technologies • Test-beam results • Future developments • Conclusions 2012/11/13 G. De Lentdecker - KEK seminar 2

Future e+e- Linear Colliders • Why ? • There are two paths for discovery: • Large Energy Range (Tevatron, LHC, HL-LHC, … ) • Direct discovery of new particles • High Precision (LEP, ILC, CLIC, … ) • Inferring new physics effects from high energy scales through precise measurements at lower energy • Combining both strategies gives much more complete understanding than either one alone • Let’s take a (random) example … 2012/11/13 G. De Lentdecker - KEK seminar 3

The Higgs • The LHC has just discovered a new particle with a mass around 125-126 GeV/c 2 , consistent with the Brout-Englert- Higgs boson. But is it the SM Higgs boson ? Gauge Symetry Breaking Principle & We can Mass Generation now test it Established by precision EWK studies Any deviation from the straight line would indicate Relativistic Quantum Field theory BSM physics ! 2012/11/13 G. De Lentdecker - KEK seminar 4

Why precision ? Assumed luminosities: LHC = 14 TeV, 300fb -1 (*) HLC = ILC 250 GeV, 250fb -1 ILC = ILC 500 GeV, 500fb -1 ILCTeV = ILC 1 TeV, 1000fb -1 (*) 300fb -1 à ~ 2020 5% deviation band from 1 σ confidence intervals SM prediction of the coupling M. Peskin arXiv:1207.2516v2 [hep-ph] 2012/11/13 G. De Lentdecker - KEK seminar 5

Experiment concept for ILC • “Visualize events as viewing Feynman diagrams” • We should be able to reconstruct any final state in term of partons (quarks, leptons, gauge bosons) • Concept of particle flow (PF) • High granularity calorimetry: 1000 x LHC channels " % ! 1 ' = 0.1 ( LHC • High resolution tracking : $ ' p t $ # & • Hermiticity: – Down to 10 mrad or lower – Everything incl. HCAL in Solenoid (B>3.5 T) 2012/11/13 G. De Lentdecker - KEK seminar 6

Bird’s Eye View of the ILC Accelerator Damping ring Detectors Accelerator tunnel e+e- main linac Illustration by Rei Hori Energy: 250 GeV + 250 GeV Length : 11km + 11km # of DRFS Klystron = 7280 # of Cryomodules = 1680 # of Cavities = 14560 2012/11/13 G. De Lentdecker - KEK seminar 7

Detectors design • Si vertex detector • Large TPC (L=4.3m, Ø=3.6m) • Si envelope (in- & outside) • Precise calor. impact • Calorimeter • Muon chambers SiD • All Si tracker ~10 discrete position measurements with ILD σ r φ ~10 µm and a lever arm of ~1m in a 5T magnetic field 2012/11/13 G. De Lentdecker - KEK seminar 8

TPC principle Readout plane B drifting e - E Projected trajectory ionizing particle 2012/11/13 G. De Lentdecker - KEK seminar 9

ILD TPC with MPGD • Micro Pattern Gas Detector (MPGD) instead of MWPC for the electron amplification stage: Not limited by the ExB effects MICROMEGAS OR GEM (Gas ElectronMultiplier) • 200 hits/track • δ 1/pt ~ 9 10 -5 /GeV/c (TPC only) • δ 1/pt ~ 2 10 -5 /GeV/c (Full Tracker) • σ (r φ ) < 100 µm • Rad length: 0.04X 0 – 0.25 X 0 • dE/dx resol ~ 5% 2012/11/13 G. De Lentdecker - KEK seminar 10

MICROMEGAS & GEM MICROMEGAS GEM ~50 µ m ~50 kV/cm ~1 kV/cm ~100 µ m ~50 kV/cm 2012/11/13 G. De Lentdecker - KEK seminar 11

The Large Prototype TPC (LPTPC) • Dimensions: • Length = 61cm • Diameter = 77cm • Endplate : • Aluminium • Can accommodate 7 detectors/dummy modules • GEM and Micromegas modules have same shape à à interchangeable MICROMEGAS/Multi-GEM 2012/11/13 G. De Lentdecker - KEK seminar 12

The field cage Radiation Length: 1.31% of X 0 • HV : up to 20kV . 2012/11/13 G. De Lentdecker - KEK seminar 13

New endplate Endplate material budget: • readout : 5% X 0 • Cooling : 2% X 0 • Power cables :10% X 0 • Mechanical structure : 8% X 0 New lighter endplate, space frame, completed end of March 2012: Old endplate 16,9 % X 0 New endplate 7,5 % X 0 2012/11/13 G. De Lentdecker - KEK seminar 14

DESY set-up Cosmic Trigger setup e - • LPTPC slided into a superconducting solenoid of up to 1.25 T • 1 < p < 6 GeV/c e - e - 2012/11/13 G. De Lentdecker - KEK seminar 15

DESY set-up developments • LCTPC Collaboration with EUDET and AIDA : DESY – KEK collab PCMAG upgraded: new crycoolers and closed cooling cirtcuit (not shown here) Thanks to KEK-IPNS cryo. Group & KEK cryo. center 3D moving table + detector, electronics, developments … 2012/11/13 G. De Lentdecker - KEK seminar 16

Tested MPGD technologies • 4 MPGD readout options are tested with the LPTPC: • Analog TPC (Subject to gas gain fluctuation in the gas amplification) • Multi layer GEM with standard pads – The charge is spread on the pad plane by diffusion • MICROMEGAS with resistive-anode pads – To spread the very narrow avalanche charge on the pad plane • Muli layer GEM with pixel readout – To cope with high occupancy • Digital TPC (Free from gas gain fluct. Expect improvement on position resolution by 20-30%) • Gridpix – pixel device with implemented Micromegas mesh (Timepix of the pixel size of 55 µ m) detecting individual primary electrons with 100% efficiency. 2012/11/13 G. De Lentdecker - KEK seminar 17

Multi layer GEM with standard pads • 2-3 layers of GEM provide sufficient gas gain O(1000) for low noise electronics • The gap between the GEMs and the E fields determine the charge spread à determine the point resolution • 2 types of GEM modules have been successfully tested: • Asian GEM • Double thick (100µm) GEMs • Stretching to minimise dead region on the sides. • DESY GEM • Triple CERN GEM With thin (1mm) ceramic frame) 2012/11/13 G. De Lentdecker - KEK seminar 18

Asian GEM Set-up @ DESY • ALTRO chip (ALICE TPC Read Out) has 16 channels • Digitize and buffer the signal 5152 pads of 1.2 x 5.4 mm 2 • Perform zero-suppression (28 staggered rows) • 1 FEC has 8 ALTRO chips • For LCTPC, CERN designed a new preamp: PCA16 • Tuneable gains, polarity, peaking/decay time, … 2012/11/13 G. De Lentdecker - KEK seminar 19

Some Double GEM Events 2012/11/13 G. De Lentdecker - KEK seminar 20

Spatial Resolution 2012/11/13 G. De Lentdecker - KEK seminar 21

Developments • Recent: • New segmented GEM foils (to reduce the discharge probability) • 3 modules will be tested at DESY in December 2012 • Future (2013): • New readout electronics: the SALTRO16 • Tested successfully on electronics testbench • Power pulsing demonstrated – Power consumption reduced by a factor 60 with 5 Hz cycle 25 mm 32.5 mm 2012/11/13 G. De Lentdecker - KEK seminar 22

MICROMEGAS with resistive anodes Z=20cm, 200 ns shaping • Resistive coating on top of an insulator: Continuous RC network which spreads the charge from σ (avalanche)~15 µ to mm: matching x(pad) – x(track) (mm) pad width improves position • PAD RESPONSE : Relative sensitivity fraction of ‘charge’ seen by the pad, vs x(pad)-x(track) M. Dixit, A. Rankin, NIM A 566 (2006) 28 2012/11/13 G. De Lentdecker - KEK seminar 23

First MICROMEGAS tests • 3 bulk MICROMEGAS modules tested • Regular anodes • Resistive anodes (carbon loaded kapton) with a resistivity ~ 5-6 M Ω / □ • Resistive anodes (resistive ink) with a resistivity ~ 1-2 M Ω / □ • 1726 (24x72) pads of ~3x7 mm ² • T2K AFTER-based electronics (72 ch./chip): • low-noise (700 e-) pre-amplifier-shaper • 100 ns to 2 µ s tunable peaking time • full wave sampling by SCA 2012/11/13 G. De Lentdecker - KEK seminar 24

Some events B=1T, T2K gas: Ar/CF 4 /iso-C 4 H 10 (95:3:2) 2012/11/13 G. De Lentdecker - KEK seminar 25

Spatial resolution • Measured drift velocity (E drift = 230 V/cm), 7.56 ± 0.02 cm/µs • Magboltz: 7.548 ± 0.003 cm/µs for Ar/CF 4 /iso-C 4 H 10 /H 2 O (95:3:2:100ppm) 2012/11/13 G. De Lentdecker - KEK seminar 26

New Compact T2K electronics • New resistive anode with improved grounding • Compact T2K electronics directly mounted on the backside of the MICROMEGAS module Remove protection Remove the packaging Transfer power regulation and ADC to the mezzanine module card. Summer 2012: 6 modules mounted on LPTPC 2012/11/13 G. De Lentdecker - KEK seminar 27

First results online offline • Also improvements in offline track reconstruction: • Uses now KalmanFilter (K. Fujii) in MarlinTPC (ILCSOFT) framework 2012/11/13 G. De Lentdecker - KEK seminar 28

Study of the cracks • Having now almost the full LPTPC endplate equipped with modules allow to study the features of the Large TPC prototype Study the hit reconstruction efficiency Outside crack at or near the crack: take data with beam, moving by steps of 2mm Beam In crack direction Pad-row number (3x24=72) Upper crack Lower crack Hits with ADC>150, event w/. 1 track 2012/11/13 G. De Lentdecker - KEK seminar 29