18 mai 2009
The main focus of the particle physics team is to provide the theory for precision tests of the standard model (SM) in lower energy experiments. Recently, much experimental effort has been dedicated to study the Cabibbo-Kobayashi-Maskawa (CKM, Nobel prize 2008) mechanism for the mixing of quark flavors and for CP violation. The relevant theory requires contending with nonperturbative strong interaction effects, which we have strong evidence to believe are described by quantum chromodynamics (QCD). At low energies, the coupling constant of QCD becomes large, the physics becomes highly nonlinear and the elementary quarks and gluons are confined into complicated bound state hadrons. Thus, the efforts of the team are mainly devoted to the development and application of analytical and numerical approaches (chiral perturbation theory, large-Nc limit, heavy-quark and soft-collinear effective theories, large scale numerical simulations,...) to provide a better understanding of these nonperturbative effects. Since these same techniques are relevant for obtaining predictions at low energies in models which go beyond the SM, we apply them there as well.
The particle physics team is headed by Laurent Lellouch (DR2) and is composed of the other permanent researchers Jérôme Charles (CR1), Marc Knecht (DR2 and CPT director), Eduardo de Rafael (DR1 emeritus). During the last four years the team has trained 8 PhD students (J.-Ph. Aguilar, J. Babel, E. Bazzali, S. Friot, J. Frison, D. Greynat, A. Portelli, G. Vulvert) and hosted 3 postdoctoral fellows (C. Bernicot, R. Kaiser, A. Ramos). It has also hosted medium term visitors (1 month or more), amongst which are Prof. Gernot Akemann (Brunel U,. U.K.), Prof. Claude Bernard (Washington U., USA), Dr. Christian Hoelbling (U. Wuppertal, Germany), Dr. Irinel Caprini (NIPNE, Romania), Prof. Stephen Sharpe (U. of Washington, USA).