chiral perturbation theory; dispersion relations; finite size effects; supersymmetry; flavour mixing; CP violation; Standard Model of Particle Physics; Strong interactions; Effective Field Theories
Procura Massimiliano, Stewart Iain W. (2011), Fragmentation inside an identified jet, in AIP Conf.Proc.
, 1343, 424-426.
Jain Ambar, Procura Massimiliano, Waalewijn Wouter J. (2011), Parton Fragmentation within an Identified Jet at NNLL, in JHEP
, 1105, 035-035.
Colangelo Gilberto, Durr Stephan, Juttner Andreas, Lellouch Laurent, Leutwyler Heinrich, others (2011), Review of lattice results concerning low energy particle physics, in Eur.Phys.J.
, C71, 1695-1695.
Jain Ambar, Procura Massimiliano, Waalewijn Wouter J., Fully-Unintegrated Parton Distribution and Fragmentation Functions at Perturbative $k_T$, in JHEP
Caprini Irinel, Colangelo Gilberto, Leutwyler Heinrich, Regge analysis of the pi pi scattering amplitude, in European Journal of Physics C
In particle physics there is a general effort worldwide to find effectswhich cannot be explained by the standard model (SM) - the generally accepted theory of particle interactions. This effort is carried out along two main alleys: the high-energy and the high-precision ones. By increasing theenergy of the events observed in laboratory one tries to produce newparticles, not present in the standard model. By increasing the precisionof the measurements of the decays of known particles one tries to seedeviations due to the effect of virtual particles from what the standard model predicts - in this case the evidence of new particles is only indirect.The last few years of activity in the field of experimental particlephysics have shown that more patience and perseverance are needed in thesearch for new physics. This is due both to the delayed start of the LHCand to the continuing success of the SM in describingprecision experiments - despite the steady accumulation of new data andincrease in precision. Hints of possible failures of the SM are beingdiscussed right now, as always in the last several years, but these are far from being conclusive yet. The big picture of particle physics has not changedwith respect to two years ago, when we submitted the application for aresearch project of which the present one represents the continuation.Our first goal is to improve our understanding of strong-interactionphenomena, both per se and in order to extract from experimentinformation about fundamental parameters of the SM. The tools to deal withstrong interactions are: chiral perturbation theory (CHPT), dispersionrelations, and numerical lattice calculations. Although we do not directlyperform the latter, we make CHPT calculations which help in doing thenecessary extrapolations before one can use the numerical results inconnection with phenomenology.Our second line of research concerns the interpretation of new physicssignals in low energy experiments. In this research project we adopt asupersymmetric extension of the SM as the framework in which to discussthese issues, and in particular assume that the flavor structure of thelatter is not fully arbitrary, but respects the principle of minimalflavor violation (MFV). According to this, the only sources of flavorviolations are represented by the Yukawa matrices, even in extensions ofthe SM. In this way it is possible to have controlled flavor violations(as required by experiments) without fully specifying the supersymmetricmodel.This is the line of research which provides the bridge to theLHC physics: in the framework we work in, new physics effects are providedby loops of new particles. Their masses and coupling constants determinethe size of the effects and low energy precision experiments excluderegions in the parameter space. If supersymmetry is relevant below the TeVregion, then one should find new particles in the regions of parameterspace which are allowed by low energy experiments. Conversely, once the LHC will find new particles it will be easy to predict what kind of effects toexpect in precision experiments at low energy.