Changes between Version 1 and Version 2 of Milano2010
- Timestamp:
- Apr 6, 2012, 4:33:03 PM (12 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
Milano2010
v1 v2 19 19 20 20 * [http://www.hep.phy.cam.ac.uk/theory/webber/QCDbook.html QCD and Collider Physics] by Keith Ellis, James Stirling, Bryan Webber (Cambridge Monographs, 1996). 21 * [ :FurtherReading:Perspectives on LHC physics, Ed. by G. Kane and A. Pierce].21 * [wiki:FurtherReading Perspectives on LHC physics, Ed. by G. Kane and A. Pierce]. 22 22 === MadGraph Exercises === 23 23 … … 30 30 * Register with a valid e-mail address 31 31 * Feynman diagrams. Generate a few processes (with different QED + QCD couplings) trying to guess which diagrams appear: 32 * uu~ >tt~33 * gg >tt~34 * gg >tt~h35 * uu~ >tt~bb~32 * uu~>tt~ 33 * gg>tt~ 34 * gg>tt~h 35 * uu~>tt~bb~ 36 36 * Subprocess identification. List all subprocesses contributing to: 37 * pp >h>tt~bb~38 * pp >tt~bb~39 * pp >tt~jj37 * pp>h>tt~bb~ 38 * pp>tt~bb~ 39 * pp>tt~jj 40 40 * Look at the new physics models and check the particle and interactions content. 41 41 * Advanced: Download the MG/ME package and play with the standalone version. 42 * [ :SimpleKinematics:Kinematics at the LHC]: refresh the kinematics of an hadron collider.42 * [wiki:SimpleKinematics Kinematics at the LHC]: refresh the kinematics of an hadron collider. 43 43 ==== Lecture 2: Calculate cross sections and generate events ==== 44 44 45 45 Generate events for a few selected processes and look at the plots: 46 46 47 * ttbar production with decays: pp >tt~>bb~mu+e-ve~vm48 * VV production: pp >VV>leptons, with V=Z,W.49 * Single top + Higgs: pp >tHj (QCD=0, QED=3, j=gudsc,p=gudscb). Show that there is a large negative interference between the diagrams.50 * gg >H>WW47 * ttbar production with decays: pp>tt~>bb~mu+e-ve~vm 48 * VV production: pp>VV> leptons, with V=Z,W. 49 * Single top + Higgs: pp>tHj (QCD=0, QED=3, j=gudsc,p=gudscb). Show that there is a large negative interference between the diagrams. 50 * gg>H>WW 51 51 * Weak boson fusion 52 52 53 53 Some phenomenological applications (at the parton level): 54 54 55 * [ :2Jets:Jets] : Di-jet kinematics and rates in pp collisions.56 * [ :3Jets:3 Jets] : Energy distributions in 3-jet events.57 * [http ://cp3wks05.fynu.ucl.ac.be/twiki/bin/view/Physics/WAsymm Drell-Yan] : Study the rapidity asymmetry at the Tevatron.58 * [ :tt:top production] : %$t \bar t$%production, Tevatron vs LHC.59 * [ :tprime:t' production] : %$t'$%production at the LHC.55 * [wiki:2Jets Jets] : Di-jet kinematics and rates in pp collisions. 56 * [wiki:3Jets 3 Jets] : Energy distributions in 3-jet events. 57 * [https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/WAsymm Drell-Yan] : Study the rapidity asymmetry at the Tevatron. 58 * [wiki:tt top production] : $t \bar t$ production, Tevatron vs LHC. 59 * [wiki:tprime t' production] : $t'$ production at the LHC. 60 60 ==== Lecture 3: The full simulation chain and advanced features ==== 61 61 … … 69 69 70 70 Choose a channel and investigate signal and background: 71 1. The 4 lepton final state: %$pp \to H\to Z Z \to e^+e^- \mu^+ \mu^-$%71 1. The 4 lepton final state: $pp \to H\to Z Z \to e^+e^- \mu^+ \mu^-$ 72 72 * Signal 73 73 * Events: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l-signal.lhe.gz Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l-signal.lhco.gz Detector Level] … … 76 76 * Events: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l.lhe.gz Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l.lhco.gz Detector Level] 77 77 * Plots: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l-lhe.pdf Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/h4l-lhco.pdf Detector Level] 78 1. The 2 lepton + missing Et final state: %$pp \to H\to W^+ W^- \to e^- \bar \nu_e \mu^+ \nu_\mu $78 1. The 2 lepton + missing Et final state: $pp \to H\to W^+ W^- \to e^- \bar \nu_e \mu^+ \nu_\mu $ 79 79 * Signal 80 80 * Events: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-signal.lhe.gz Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-signal.lhco.gz Detector Level] … … 83 83 * Events: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-background.lhe.gz Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-background.lhco.gz Detector Level] 84 84 * Plots: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-background-lhe.pdf Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/hww-background-lhco.pdf Detector Level] 85 1. Top associated production %$pp \to t\bar tH$% with %$H \to b \bar b$%85 1. Top associated production $pp \to t\bar tH$ with $H \to b \bar b$ 86 86 * Signal + Background samples: 87 87 * Events: [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/ttbb.lhe.gz Parton Level] [http://cp3wks05.fynu.ucl.ac.be/twiki/pub/Physics/DiscoverTheHiggs/ttbb.lhco.gz Detector Level] … … 103 103 104 104 Useful extra information: 105 * In the plots %$H_T=\sum ||p_T^{vis}|| + E_T^{miss}$%.105 * In the plots $H_T=\sum ||p_T^{vis}|| + E_T^{miss}$. 106 106 * A SM-like Z' would decay (more or less democratically) into: jet jet (uu~,cc~,dd~,ss~,bb~), t tbar (tt~), lept+lept- (e+e-,mu+mu-,ta+ta-), neutrino anti-neutrino (ve ve~,vm vm~,vt vt~). It could also have couplings to SM W and Z, and in that case would decay in to ZZ and W+W-. 107 107 * An Higgs couple to particles with a strength which is proportional to the particle masses. A SM-like heavy H would decay in to t tbar (tt~), W+W-, ZZ. … … 115 115 * Importance sampling via an analytic transformation 116 116 * Von Neumann's rejection method : plain and improved 117 * Phase space for 1 - >n particles117 * Phase space for 1 -> n particles 118 118 * Vegas 119 119 * Top decay : comparison among the various methods 120 * qq - >tt production120 * qq -> tt production 121 121 122 122 All exercises are presented and solved this Mathematica Notebook: [attachment:mc101.nb mc101.nb]. Reference: [http://www.slac.stanford.edu/spires/find/hep/www?eprint=hep-ph/0006269 Introduction to MC methods], by [http://wwwthep.physik.uni-mainz.de/~stefanw/ Stefan Weinzierl] … … 134 134 135 135 136