Beyond The Standard Model

The present lectures contain an introduction to possible new physics beyond the Standard Model. Having in mind first of all accelerator experiments of the nearest future we concentrate on supersymmetry, a new symmetry that relates bosons and fermions, as the first target of experimental search. Since supersymmetry is widely covered in the literature, we mostly consider novel developments and applications to hadron colliders. We describe then the so-called extra dimensional models in less detail and discuss their possible manifestations.Comment: 52 pages, 51 eps figures, Lectures given at the European School on High Energy Physics, May-June 2004, Sant Feliu de Guixols, Spai

Renormalization Properties of Softly Broken SUSY Gauge Theories

In the present review we show that renormalizations in a softly broken SUSY gauge theory are not independent but directly follow from those of an unbroken or rigid theory. This is a consequence of a treatment of a softly broken theory as a rigid one in external spurion superfield. This enables one to get the singular part of effective action in a broken theory from a rigid one by a simple modification of the couplings. Substituting the modified couplings into renormalization constants, RG equations, solutions to these equations, approximate solutions, fixed points, etc., one can get corresponding relations for the soft terms by a simple Taylor expansion over the Grassmannian variables. Some examples including the MSSM in low and high $\tan\beta$ regime, SUSY GUTs and the N=2 Seiberg-Witten model are considered.Comment: LaTeX, 25pp, 2 eps figures. Talk at "Continuous Advances in QCD 2002/Arkadyfest

IS (Low Energy) SUSY STILL ALIVE?

Supersymmetry, a new symmetry that relates bosons and fermions in particle physics, still escapes observation. Search for supersymmetry is one of the main aims of the Large Hadron Collider. The other possible manifestation of supersymmetry is the Dark Matter in the Universe. The present lectures contain a brief introduction to supersymmetry in particle physics. The main notions of supersymmetry are introduced. The supersymmetric extension of the Standard Model -- the Minimal Supersymmetric Standard Model -- is considered in more detail. Phenomenological features of the Minimal Supersymmetric Standard Model as well as possible experimental signatures of supersymmetry at the Large Hadron Collider are described. The present limits on supersymmetric particles are presented and the allowed region of parameter space of the MSSM is shown.Comment: 59 pages, 35 figures, PDFLatex, Lectures at the European School of High-Energy Physics, June 2012, Anjou, Franc