The high energy experiments at LHCAtlas, CMS and LHCb

Markus K. Kohler

18.11.2010LHC seminar

Why high energy experiments?

questions in (fundamental) physics

I origin of mass

I additional dimensions

I dark part of the universe

I many more ...

High energy experiments at LHC 22

Why high energy experiments?

I opportunity to explore thesmall-scale structure ofmatter

I detectors are needed forthe investigation of

1. time evolution2. behaviour/mechanism

of interaction

of the created matter

High energy experiments at LHC 33

Why high energy experiments?

I opportunity to explore thesmall-scale structure ofmatter

I detectors are needed forthe investigation of

1. time evolution2. behaviour/mechanism

of interaction

of the created matter

High energy experiments at LHC 33

The role of the detector

detector requirements

provide information to

I count/distinguish

I track

I characterize

particles.

High energy experiments at LHC 44

The role of the detector

detector requirements

provide information to

I count/distinguish

I track

I characterize

particles.

High energy experiments at LHC 44

Outline

I detector structures

I ATLAS

I CMS

I LHCb

High energy experiments at LHC 55

Possible detector structure in HEP

systematics

I low density → high density

I Track density ∝ 1/r2

I high precision → low precision

High energy experiments at LHC 66

Inner tracking chambers

I ionizing effects on the material particles pass through

I vertex informationI silicon

1. Pixel (high resolution/fast readout)2. strip

High energy experiments at LHC 77

Calorimeter

I measures the energy (deposit) of electromagnetic or hadronicinteracting particles

I materials are used, which interact electromagnetic or hadronic

Working principle

I two layers

1. absorber (dense)2. collector (active)

High energy experiments at LHC 88

Calorimeter

I measures the energy (deposit) of electromagnetic or hadronicinteracting particles

I materials are used, which interact electromagnetic or hadronic

Working principle

I two layers

1. absorber (dense)2. collector (active)

High energy experiments at LHC 88

The experiments of LHC

High energy experiments at LHC 99

ATLAS and CMS

A Toroidal LHC ApparatuS Compact Muon Solenoid

High energy experiments at LHC 1010

ATLAS and CMS

physics program

I Higgs boson

I supersymmetry (LSP)

I extra dimensions

detector requirements

I identification of hadrons,leptons and photons

I hadrons and jets at highpseudo rapidity

I reasonable momentumresolution up to TeV/cscale

High energy experiments at LHC 1111

ATLASA Toroidal LHC ApparatuS

facts

Size 25×25×46m3

Weight 7000 tonnesmag. field 2 T/4 T

High energy experiments at LHC 1212

ATLASglobal design

High energy experiments at LHC 1313

ATLASdesign

I Inner detector

1. Pixel detectors2. Semiconductor tracker

(SCT)3. Transition Radiation

Tracker (TRT)

High energy experiments at LHC 1414

ATLASdesign

I calorimeter

1. electromagnetic(yellow)

2. hadronic (grey)

High energy experiments at LHC 1515

ATLAScalorimetry

electromagnetic

1. accordion (LAr|lead)

2. forward (LAr|copper)

hadronic

1. tile (iron|scintillating)

2. end-cap (LAr|copper)

3. forward (LAr|tungsten)

High energy experiments at LHC 1616

ATLASdesign

Muon spectrometer and magnetic field

High energy experiments at LHC 1717

ATLASrange in pseudo rapidity

High energy experiments at LHC 1818

ATLASRead out devices

comparison of the detectors

Detector Read out channels

Pixel >82 mioSCT >3.1 mioMuon det. comp. >300.000

High energy experiments at LHC 1919

ATLASperformance

High energy experiments at LHC 2020

ATLASperformance

High energy experiments at LHC 2020

CMSCompact Muon Solenoid

facts

Size 21×15×15m3

Weight 12500 tonnesmag. field 4 T / 2.8 T

High energy experiments at LHC 2121

CMSglobal design

High energy experiments at LHC 2222

CMSdetector system

I global detector structure

I particle identification and tracking

High energy experiments at LHC 2323

CMSdetector system

I global detector structure

I particle identification and tracking

High energy experiments at LHC 2323

CMSMuon detector system

detector types

I Drift Tube

1. barrel2. σrφ ∝ 100µm

I Cathode Strip Chambers

1. end-cap2. trapeziodal shape3. σφ ∝ 100µm

I Resistive Plate Chamber

1. barrel + end-cap2. weak σx3. very good σt4. trigger decision

High energy experiments at LHC 2424

CMSelectron efficiency and pseudo rapidity range

H → ZZ∗ → 4e

Efficiency =Nrec

Ngen

CMS TDR,2006

High energy experiments at LHC 2525

CMSdimuon candidate

High energy experiments at LHC 2626

CMSperformance

High energy experiments at LHC 2727

LHCbLHC beauty

physics program

I CP violation

I measurement of CKMparameter

I quarkonia

I B physics, rare B decays

detector requirements

I particle identification

I vertex resolution

I secondary vertex trigger

High energy experiments at LHC 2828

LHCbLHC beauty

facts

Size 5×5×20 m3

forward direction10 < θ < 300 mrad1.9 < η < 4.9

High energy experiments at LHC 2929

LHCbLHC beauty

High energy experiments at LHC 3030

LHCbVErtex LOcater VELO

details

I 1.5 ≤ η ≤ 4.9

I distance to beam 5 mm

I σxyz ≈ 10µm

I embedded in a secondvacuum (10−4 mbar)

High energy experiments at LHC 3131

LHCbperformance

High energy experiments at LHC 3232

Summary

The detector systems at LHC

I are commissioned succesfully (pp and PbPb)

I could proof their performance

I did show interesting results

I will provide interesting results

High energy experiments at LHC 3333