LHCb

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The accelerator chain of the Large Hadron Collider (LHC)
LHC experiments
ATLAS	A Toroidal LHC ApparatuS
CMS	Compact Muon Solenoid
LHCb	LHC-beauty
ALICE	A Large Ion Collider Experiment
TOTEM	Total Cross Section, Elastic Scattering and Diffraction Dissociation
LHCf	LHC-forward
LHC preaccelerators
p and Pb	Linear accelerators for protons and Lead
(not marked)	Proton Synchrotron Booster
PS	Proton Synchrotron
SPS	Super Proton Synchrotron

The LHCb (standing for "Large Hadron Collider beauty" where "beauty" refers to the bottom quark) experiment is one of six particle physics detector experiments being constructed on the Large Hadron Collider accelerator at CERN. LHCb is a specialist b-physics experiment, particularly aimed at measuring the parameters of CP violation in the interactions of b-hadrons (heavy particles containing a bottom quark).

[edit] The LHCb detector

The fact that both B hadrons are predominantly produced in the same forward cone as B meson production is exploited in the layout of the LHCb detector. The LHCb detector is a single arm forward spectrometer with a polar angular coverage from 10 mrad to 300 mrad in the horizontal and 250 mrad in the vertical plane. The asymmetry between the horizontal and vertical plane is determined by a large dipole magnet with the main component in the vertical direction.

The vertex detector (known as the vertex locator or VELO) is built around the proton interaction region. It is used to measure the particle trajectories close to the interaction point in order to precisely separate primary and secondary vertices, e.g. for B-tagging.

Directly after the vertex detector, a RICH-1 (a Ring imaging Cherenkov detector) is located. It is used for particle identification of low-momentum tracks.

The main tracking system is placed before and after the dipole magnet. It is used to reconstruct the trajectories of charged particles and to measure their momenta.

Following the tracking system is RICH-2. It allows the identification of the particle type of high-momentum tracks.

The electromagnetic and hadronic calorimeters provide measurement of the energy of electrons, photons and hadrons. These measurements are used at trigger level to identify the particles with high transversal moment (high-Pt particles).

The muon system is used to trigger on muons in the events.