Linear Collider Detector (LCD) project overview Outline: Introduction to CLIC accelerator CLIC physics potential Detector requirements, ILC and CLIC Current activities and R&D plan Summary Lucie Linssen PH senior staff meeting, March 4th 2010 http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

General LCD Context The LHC will determine the future of high-energy physics. The linear collider is one of the best options to complement and extend the LHC programme New physics expected in TeV energy range E.g. motivated by particle astrophysics (dark matter) Higgs, Supersymmetry, extra dimensions, …? LHC will indicate what physics, and at which energy scale: Is 500 GeV enough (ILC) Is there a need for multi TeV? (CLIC) The CERN “Linear Collider Detector” project addresses both ILC and CLIC, though current focus is on the preparation of the CLIC physics/detector CDR, due for April 2011 http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

ILC and CLIC in a few words… linear collider, producing e+e- collisions CLIC ILC Based on superconducting RF cavities Gradient 32 MV/m Energy: 500 GeV, upgradeable to 1 TeV (lower energies also considered) Detector studies focus mostly on 500 GeV Based on 2-beam acceleration scheme Gradient 100 MV/m Energy: 3 TeV, though will probably start at lower energy (~0.5 TeV) Detector study focuses on 3 TeV Luminosities: few 1034 cm-2s-1 http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

The CLIC Two Beam Scheme Drive Beam supplies RF power 12 GHz bunch structure low energy (2.4 GeV - 240 MeV) high current (100A) Main beam for physics high energy (9 GeV – 1.5 TeV) current 1.2 A No individual RF power sources http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

The full CLIC scheme Not to scale! http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

CLIC physics up to 3 TeV What can CLIC provide in the 0.5-3 TeV range? In a nutshell… Higgs physics: Complete study of the light standard-model Higgs boson, including rare decay modes (rates factor ~5 higher at 3 TeV than at 500 GeV) Higgs coupling to leptons Study of triple Higgs coupling using double Higgs production Study of heavy Higgs bosons (supersymmetry models) Supersymmetry: Extensive reach to measure SUSY particles And in addition: Probe for theories of extra dimensions New heavy gauge bosons (e.g. Z’) Excited quarks or leptons http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

(S)LHC, ILC, CLIC reach Gian Giudice CLIC09 http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Gian Giudice CLIC09

ILC and CLIC detector studies In several aspects the CLIC detector will be more challenging than ILC case, due to: Energy 500 GeV => 3 TeV More severe background conditions Due to higher energy Due to smaller beam sizes Time structure of the accelerator Detector studies and R&D for the ILC are most relevant for CLIC. Many years of investment in ILC e+e- physics/detector simulations, hardware R&D and detector concepts. No need to duplicate work. Therefore we have joined several Linear Collider (ILC) collaborations: ILD concept, SiD concept, CALICE, FCAL, LC-TPC + EU projects (EUDET/AIDA). http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

ILC=> CLIC detector requirements http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Validated ILC concepts CLIC detector concepts will be based on SiD and ILD. Modified to meet CLIC requirements http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

CLIC and ILC time structure CLIC time structure Train repetition rate 50 Hz CLIC CLIC: 1 train = 312 bunches 0.5 ns apart 50 Hz ILC: 1 train = 2820 bunches 308 ns apart 5 Hz http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Beam-induced background Main backgrounds: CLIC 3TeV beamstrahlung ΔE/E = 29% (10×ILCvalue) Coherent pairs (3.8×108 per bunch crossing) <= disappear in beam pipe Incoherent pairs (3.0×105 per bunch crossing) <= suppressed by strong solenoid-field γγ interactions => hadrons (3.3 hadron events per bunch crossing) In addition: Muon background from upstream linac http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Beam-induced background and time–stamping γγ=> hadron events dump 7.5 TeV in the detector for each bunch train For example: ±10 degrees jet cone and 10 nsec time stamping: => 2 GeV in the cone (barrel) and 20 GeV in the cone (end cap) http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Jean-Jacques Blaising, LAPP

At high energy physics goes in forward direction Background is also principally in forward direction. Detector optimisation needs special attention here. http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Marcel Vos, IFIC

CLIC tracking/calorimetry issues Due to beam-induced background and short time between bunches: Inner radius of Vertex Detector has to become larger (~30 mm) High occupancy in the inner regions Time-stamping is a must for almost all detectors Narrow jets at high energy Will Particle Flow Analysis still work at required precision? Calorimeter has to measure high-energy particles (leakage) 3TeV e+e-  t tbar http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Jet Energy Resolution and PFA Is an ILD-sized detector based on PFA suitable for CLIC ? Defined modified ILD+ model: B = 4.0 T (ILD = 3.5 T) HCAL = 8 ΛI (ILD = 6 ΛI) Jet energy resolution PFA EJET sE/E = a/√Ejj |cosq|<0.7 sE/Ej 45 GeV 25.2 % 3.7 % 100 GeV 28.7 % 2.9 % 180 GeV 37.5 % 2.8 % 250 GeV 44.7 % 375 GeV 71.7 % 3.2 % 500 GeV 78.0 % 3.5 % Mark Thomson Cambridge Meet “LC jet energy resolution goal [~3.5%]” for 500 GeV ! jets http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Tungsten HCAL prototype Motivation: To limit longitudinal leakage CLIC HCAL needs ~7Λi A deeper HCAL pushes the coil/yoke to larger radius (would give a significant cost and risk increase and for the coil/yoke) A tungsten HCAL is more compact than Fe-based HCAL, while resolutions are similar (increased cost of tungsten barrel HCAL compensates gain in coil cost) Prototype tungsten HCAL: check simulation in test beam Fe and W based HCAL resolutions Angela Lucaci-Timoce DESY) http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Final focus stability Final focus quadrupoles inside experiment, L* = ~3.5 m Beam focusing stability required at sub-nm level !! Daniel Schulte CLIC08. http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Engineering issues Current engineering studies mostly concentrate on the critical issue of providing a stable environment for the forward focus quadrupole QD0. Measurements in CMS and several (LHC-) underground locations have guided ideas about how to suspend QD0 within the experiment volume. These ideas are currently being worked out. see MDI talk 27/1 Alain Herve experiment tunnel Forward detector region with final focus elements Alain Herve (ETHZ), Hubert Gerwig (CERN) http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Current LCD activities Current activities concentrate on preparation for CDR Mostly simulation studies: Demonstrate that CLIC physics potential can be extracted from detector Propose ILD-type and SiD-type detectors that can do the job Concentrate on critical issues Determine required sub-detector performances to see the physics Redesign of the very forward region Take engineering aspects, cost etc into account Preparing a targeted hardware R&D plan http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Andre Sailer (CERN)

Hardware/engineering R&D LCD hardware/engineering R&D (needed beyond ILC developments): Time stamping Most challenging in vertex detector: trade-off between pixel size, amount of material and timing resolution Power pulsing In view of the 50 Hz CLIC time structure => allows for low-mass detectors Hadron calorimetry ✪ Tungsten-based HCAL (PFA calo, within CALICE) Solenoid coil Large high-field solenoid concept Reinforced conductor (building on CMS/ATLAS experience) Overall engineering design and integration studies For heavier calorimeter, larger overall CLIC detector size etc. In view of sub-nm precision required for FF quadrupoles In addition: TPC electronics development (Timepix-2, S-ALTRO✪) ✪ also in AIDA EU proposal http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Core software development Ongoing developments with involvement of PH-SFT and PH-LCD: Use of enhanced ROOT functionalities in ILC software (mostly in collaboration with DESY) Improved geometry toolkit in ILD code (CERN+DESY)✪ Improvements of hadronisation process descriptions in Geant4 (collaboration between CERN/Geant4 and CALICE) Grid processing and file catalog: we receive support from LHCb to duplicate their DIRAC system. Participation in Pandora-PFA code development (Cambridge+CERN)✪ ✪ also in AIDA EU proposal http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Summary Welcome to join CLIC has a large physics potential, complementary to LHC CLIC physics/detector studies in close collaboration with ILC Growing community both inside and outside CERN Software tools in place for adapted ILD and SiD detector models Work currently focuses on CLIC physics/detector CDR (April 2011) LCD hardware R&D is starting Welcome to join http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Thank you! CLIC_ILD detector CLIC_SiD detector http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Spare Slides http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

CLIC parameters http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Tentative long-term CLIC scenario Technology evaluation and Physics assessment based on LHC results for a possible decision on Linear Collider with staged construction starting with the lowest energy required by Physics Conceptual Design Report (CDR) Technical Design Report (TDR) Project approval ? First Beam? http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Example:…. light SM-like Higgs The cross-section at ~3TeV is very large  access to very rare decays (BR~10-4). Measure Higgs couplings to leptons, for instance with 0.5 ab-1, we expect ~70 H+- decays for Mh=120 GeV/c2, and measure the couplings with ~4% precision. 1/s log(s) http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Frederic Teubert

Example: heavy mass SUSY particles e.g. e+e- → H0A0 production e+e- → H0A0 →bƃbƃ s-channel vs t-channel cross sections √S mH,A ≈ 1 TeV Yellow dots mostly from gg Marco Battaglia http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Example: SUSY mass measurement Gian Giudice CLIC09 http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Mark Thomson http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

ILD concept adapted to CLIC Changes to the ILD detector: 20 mrad crossing angle Vertex Detector to ~30 mm inner radius, due to Beam-Beam Background HCAL barrel with 77 layers of 1 cm tungsten HCAL endcap with 70 layers of 2 cm steel plates Forward (FCAL) region adaptations Fully implemented in Mokka/Marlin Andre Sailer http://www.cern.ch/lcd Lucie Linssen, 3/3/2010

Time stamping requirements (2) Simulation example of heavy Higgs doublet H0A0 at ~1.1 TeV mass (supersymmetry K’ point) e+e-  H0A0  bbbb Signal + full standard model background + γγ=>hadron background CLIC-ILD detector: Mokka+Marlin simulation, reconstruction + kinematic fit. Zero bunch crossings MA mass resol. 3.8 GeV 20 bunch crossings MA mass resol. 5.6 GeV 40 bunch crossings MA mass resol. 8.2 GeV http://www.cern.ch/lcd Lucie Linssen, 3/3/2010 Marco Battaglia