Rechercher des projets européens

Measurement of CP violation in the B_s system at LHCb (ASYMMETRY)
Date du début: 1 janv. 2011, Date de fin: 31 déc. 2015 PROJET  TERMINÉ 

The Large Hadron collider (LHC) at CERN will be a milestone for the understanding of fundamental interactions and for the future of high energyphysics. Four large experiments at the LHC are complementarily addressing the question of the origin of our Universe by searching for so-called New Physics.The world of particles and their interactions is nowadays described by the Standard Model. Up to now there is no single measurement from laboratory experiments which contradicts this theory. However, there are still many open questions, thus physicists are convinced that there is a more fundamental theory, which incorporates New Physics.It is expected that at the LHC either New Physics beyond the Standard Model will be discovered or excluded up to very high energies, which would revolutionize the understanding of particle physics and require completely new experimental and theoretical concepts.The LHCb (Large Hadron Collider beauty) experiment is dedicated to precision measurements of B hadrons (B hadrons are all particles containing a beauty quark).The analysis proposed here is the measurement of asymmetries between B_s particles and anti-B_s particles at the LHCb experiment. Any New Physics model will change the rate of observable processes via additional quantum corrections. Particle antiparticle asymmetries are extremely sensitive to these corrections thus a very powerful tool for indirect searches for New Physics contributions. In the past, most of the ground-breaking findings in particle physics, such as the existence of thecharm quark and the existence of a third quark family, have first been observed in indirect searches.First - still statistically limited - measurements of the asymmetry in the B_s system indicate a 2 sigma deviation from the Standard Model prediction. A precision measurement of this asymmetry is potentially the first observation for New Physics beyond the Standard Model at the LHC. If no hint for New Physics will be found, this measurement will severely restrict the range of potential New Physics models.

Details