LHC Experiments at Liverpool E2V Visit – Nov 2005 Introduction Si Technology Upgrade/Maintenance Summary

Introduction Large Hadron Collider –The Large Hadron Collider (LHC) is a particle accelerator which will probe deeper into matter than ever before. Due to switch on in 2007, it will ultimately collide beams of protons at an energy of 14 TeV.

LHC at CERN Studying particle collisions is like "looking back in time", recreating the environment present at the origin of our Universe.

CERN LHC Largest experimental device on earth

Experiments Four experiments, with huge detectors, will study what happens when the LHC's beams collide. They will handle as much information as the entire European telecommunications network does today! –ATLAS –ALICE –CMS –LHCb Liverpool is building key component for two of these –ATLAS and LHCb

ATLAS Scale!

ATLAS Tracker Bending of particles in magnutic field allows calculation of momentum and charge Reconstruct Collisions

ATLAS SCT Tracker allows reconstruction, in 3D, of collision –40MHz –Spatial precision <10microns Si strips and pixels –Barrel –Endcap One of most expensive detector subsystems ever built –>$100m

ATLAS SCT at Liverpool Design of Si strips Protype hybrids Mechanics Modules Assembly

ATLAS Endcap Statistics Area of Si ~ 10m 2 –4000 diced sensors Number of electronic channels –3million Expected lifetime ~ 8 years

ATLAS totals SCT strips (barrel and endcap) –8000 sensors –6 million channels SCT barrel pixels –1500 modules –90million channels 50 micron by 300/400 microns

ATLAS Summary Liverpool built one of the two endcaps for ATLAS Integral to entire programme from concept, design, prototype and construction

LHCb Experiment focusses on studying difference between matter and anti-matter –Superb tracking and vertexing required –Radiation hard Vertex detector and principal tracking device (VELO) being built By Liverpool

LHCb Vertex Locator VELO The VELO is in a vacuum 8mm from the LHC beam. 175,000 silicon strips record collisions at 40MHz.

VELO Detectors being built now 4cm

VELO Much smaller than SCT – channels –0.1m 2 of Si Specialized –N-in-n strips rad hard to p/cm sensors at cost of approx $4000/sensor

VELO Will be fully replaced in ~ 3 years and again in 6 years –Partial replacement ~ 10% year –First full replacement will be a more radiation hard substitute Full size n-in-p prototype built After 6 years we are looking at a $20m upgrade from strips to pixels –Liverpool starting studies

Summary Liverpool involved in a major way in 2 of the major experiments at LHC Building major tracking detector subsystems Continuous of programme of R&D and replacement over 10 years –See talk on SLHC