Basics of QCD for the LHC, Cern Latin American School 2013
4 Lectures are given on QCD and MC's developments for the LHC.
The PDF of the lectures be found here:
QCD1 : Intro and QCD fundamentals
QCD3: QCD in the initial state
QCD4: From accurate QCD to useful QCD
The examples and exercises are related to physics at the LHC.
Basic aspects of QCD
Various Tests and exercises
A collection of test, exercises, and web applications on pQCD can be found in QCD-exercises.pdf.
Exercise on recursive relations
Think about the computation of q \bar q + n \gamma in a recursive way, by trying not calculate the same quantities twice. Show that the complexity of the calculation goes from n! (factorial) to 2{n-1} (exponential) .
Going NLO
- pp>H at LO (1-loop): details of the calculation (Mathematica Notebook) HiggsGG-LO-mtfinite.nb
- pp>H at NLO: details of the calculation (Mathematica Notebook) higgsGG-NLO.nb
- pp>H at NLO: cross section evaluation for the LHC (Mathematica Notebook+PDF libraries to be compiled) phenHiggs.tar.gz.
A summary of the results can be found in QCDHiggs.pdf.
Selected exercises on QCD that can be solved with a Matrix Element generator.
- Radiation from heavy quarks: the dead cone in $e+e- \to Q \bar Q g$.
- Spin of the gluon: Vector vs scalar in the angular correlations of $ e+ e- \to$ 4 jets.
- Jets : Di-jet kinematics and rates in pp collisions.
- 3 Jets : Energy distributions in 3-jet events in pp collisions.
- top production : $t \bar t$ production, Tevatron vs LHC.
- Drell-Yan: rapidity asymmetry at the Tevatron and LHC.
- Spin correlations in top decay, by Bryan Webber.
Monte Carlo integration
A short introduction to the techniques of Monte Carlo integration. Exercises proposed during lecture are collected in this Mathematica Notebook: mc101.nb.
LHC Phenomenology
- SM Higgs discovery at the LHC: Three important channels
- Simple Black Boxes: New gauge bosons
How to familiarize with MadGraph
All exercises proposed can be "solved" or checked with MadGraph / MadEvent. Here is how to familiarize with the code.
- Logon to the MadGraph web site and register.
- Familiarize with the code by generating a few processes in QED and QCD trying to guess which diagrams appear. What is the minimum number of jets have to be asked for in $e+e-$ collisions so that the triple gauge vertex appear?
- Look at the new physics models and check the particle and interactions content.
- Generate events for a few selected processes and look at the plots:
- ttbar production with decays: pp>tt~>bb~mu+e-ve~vm
- VV production: pp>VV> leptons, with V=Z,W.
- Single top + Higgs: pp>tHj (QCD=0, QED=3, j=gudsc,p=gudscb). Show that there is a large negative interference between the diagrams
-- Main.FabioMaltoni - 2013-03-03
Attachments (5)
- QCDHiggs.pdf (322.1 KB ) - added by 12 years ago.
- QCD1.pdf (3.3 MB ) - added by 12 years ago.
- QCD2.pdf (2.9 MB ) - added by 12 years ago.
- QCD3.pdf (2.8 MB ) - added by 12 years ago.
- QCD4.pdf (3.7 MB ) - added by 12 years ago.