## Academic Training Lectures - QCD for Postgraduates

by Giulia Zanderighi (University of Oxford)**Monday 12 to Friday 16 April 2010**

From 11:00 to 12:00 - Main Auditorium, Bldg. 500-1-001

**Monday 12 - Modern QCD - Lecture 1**

Starting from the QCD Lagrangian we will revisit some basic QCD concepts and derive fundamental properties like gauge invariance and isospin symmetry and will discuss the Feynman rules of the theory. We will then focus on the gauge group of QCD and derive the Casimirs CF and CA and some useful color identities.

**Tuesday 13 - Modern QCD - Lecture 2**

We will start discussing the matter content of the theory and revisit the experimental measurements that led to the discovery of quarks. We will then consider a classic QCD observable, the R-ratio, and use it to illustrate the appearance of UV divergences and the need to renormalize the coupling constant of QCD. We will then discuss asymptotic freedom and confinement. Finally, we will examine a case where soft and collinear infrared divergences appear, will discuss the soft approximation in QCD and will introduce the concept of infrared safe jets.

**Wednesday 14 - Modern QCD - Lecture 3**

We will introduce processes with initial-state hadrons and discuss parton distributions, sum rules, as well as the need for a factorization scale once radiative corrections are taken into account.

We will then discuss the DGLAP equation, the evolution of parton densities, as well as ways in which parton densities are extracted from data.

**Thursday 15 - Modern QCD - Lecture 4**

We will consider some processes of interest at the LHC and will discuss the main elements of their cross-section calculations. We will also summarize the current status of higher order calculations.

**Friday 16 - Modern QCD - Lecture 5**

We will introduce and discuss in some detail the two main classes of jets: cone type and sequential-recombination type. We will discuss their basic properties, as well as more advanced concepts such as jet substructure, jet filtering, ways of optimizing the jet radius, ways of defining the areas of jets, and of establishing the quality measure

of the jet-algorithm in terms of discriminating power in specific searches. Finally we will discuss applications for Higgs searches involving boosted particles.