Cambridge LHCb Group

Will Barter, Harry Cliff, Jordi Garra Tico, Val Gibson, Sam Gregson, Susan Haines, Chris Jones, Nicola Mangiafave, David Ward, Stephen Wotton, Simon Wright

We are members of the CERN LHCb collaboration. LHCb is an experiment at the CERN LHC collider, currently taking data, which is being used to investigate the decays of B-particles (particles containing b-quarks) and so provide an insight into the phenomenon of CP-violation. The collaboration comprises about 350 physicists and engineers from more than 40 institutes from all over the world.

What is CP violation?

One of the outstanding puzzles in particle physics and cosmology is the dominance of matter over antimatter in the observable universe. In the Big Bang, matter and antimatter would have been produced in equal amounts. However, a minute flaw in the symmetries of nature resulted in the matter-dominated universe we know today. The phenomenon that distinguishes matter from antimatter is called CP violation and, although it is now well established, its origin remains one of the most compelling issues in particle physics.

What do we do?

We are engaged in an active experimental program in which we are investigating the properties of B-particle decays, how they can best be used to measure the CP-violation parameters and how to exploit the design of the LHCb apparatus to maximise the sensitivity of these measurements.

In our experimental work we have collaborated closely with other UK institutes and CERN to build the Ring Imaging Cherenkov (RICH) detectors for LHCb. These detectors allow us to distinguish between the different types of particles produced in high energy proton-proton collisions. To do this, we exploit the Cherenkov effect in which photons are emitted by charged particles when the particle speed exceeds the local speed of light. These photons from this exceedingly feeble source are detected by extremely sensitive and high speed electronic detection systems which we have helped to design, test and build. The Cambridge LHCb group is primarily involved in the following research:

• Testing hybrid photon detectors (HPDs) and Multi-anode Photomultipliers (MaPMTs)
  
  • doi:10.1016/j.nima.2009.02.011
  • doi:10.1016/j.nima.2007.01.100
  • doi:10.1016/j.nima.2003.09.062
  • doi:10.1016/S0168-9002(98)00291-5
• Designing and building L1 readout electronics for the RICHs
• Software development for event simulation and reconstruction
• RICH pattern recognition for particle ID
• Physics analysis studies

More information

You can find out more about the LHCb experiment by reading :-

• Our letter of intent (August 1995) (PDF)
• Technical Proposal (February 1998) (PDF)
• Technical Design Reports (2000-2005)
• The LHCb Detector Paper (JINST 2008)
• LHCb Public Notes