== 2018 CERN Summer student workshop  ==

== Animations ==
   * [http://madgraph.phys.illinois.edu/Event/ Interactive Flash version] Note you may want to zoom in!
   * [http://mgx0.hep.uiuc.edu/Event/fast_collisionx6.avi Fast movie (.avi) of collision]
   * [http://mgx0.hep.uiuc.edu/Event/collision.mov Guided movie (.mov) of collision]


=== Exercises ===
Discover the Higgs at the LHC:
   * Find the best prediction for Higgs production at the LHC [http://maltoni.web.cern.ch/maltoni/TeV4LHC/index.html here].
   * Find the Higgs branching ratios [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h-br.pdf here]. 

Choose a channel and investigate signal and background:

   1. The 4 lepton final state: $pp \to H\to Z Z \to e^+e^- \mu^+ \mu^-$
      * Signal 
         * Events:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-signal.lhe.gz Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-signal.lhco.gz Detector Level] 
         * Plots: [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-signal-lhe.pdf Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-signal-lhco.pdf Detector Level] 
      * Background 
         * Events:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l.lhe.gz Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l.lhco.gz Detector Level] 
         * Plots: [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-lhe.pdf Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-lhco.pdf Detector Level] 
   1. The 2 lepton + missing Et final state: $pp \to H\to W^+ W^- \to e^- \bar \nu_e \mu^+ \nu_\mu $
      * Signal 
         * Events:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/hww-signal.lhe.gz Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/hww-signal.lhco.gz Detector Level] 
         * Plots: [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/hww-signal-lhe.pdf Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/hww-signal-lhco.pdf Detector Level] 
      * Background 
         * Events:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/hww-background.lhe.gz Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-background.lhco.gz Detector Level] 
         * Plots: [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-background-lhe.pdf Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/h4l-background-lhco.pdf Detector Level] 
   1. Top associated production $pp \to t\bar tH$ with $H \to b \bar b$
      *  Signal + Background samples:
         * Events:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/ttbb.lhe.gz Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/ttbb.lhco.gz Detector Level] 
         * Plots: [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/ttbb-lhe.pdf Parton Level] [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/ttbb-lhco.pdf Detector Level] 

=== The Challenge ===

Three "black boxes" are given, in the form of event files in the LHC Olympics format and a series of selected plots:

   * Box A : [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/A.lhco.gz Events]  Plots:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/A-lhe.pdf Parton level]  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/A.pdf Detector level]
   * Box B : [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/B.lhco.gz Events]   Plots:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/B-lhe.pdf Parton level]   [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/B.pdf Detector level]
   * Box C : [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/C.lhco.gz Events]  Plots:  [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/C-lhe.pdf Parton lelve]   [https://cp3.irmp.ucl.ac.be/projects/madgraph/attachment/wiki/CernSummerSchool/C.pdf Detector level]

Black boxes contain only signal events. The students are asked to pair up the boxes above with the following models and also answer to the questions:

   * Model 1 : Extra Z (zp) : What its mass? Does it have Standard Model couplings to fermions? 
   * Model 2 : Heavy Scalar (h): What its mass?  Is it a SM Higgs?
   * Model 3 : Extra W (wp+ or wp-) : What its mass? Does it have Standard Model couplings to fermions? 
 
Useful extra information:
   * In the plots $H_T=\sum ||p_T^{vis}|| + E_T^{miss}$.
   * 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-.
   * 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.   
   * A SM-like  W'+ would decay into: jet jet (ud~,cs~), t b (tb~), lept neutrino (e+ ve , mu+ vm, ta+ vt). It could also have couplings to SM W and Z, and in that case would decay in to ZW.