=== Discover New gauge bosons at the LHC ===

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


   * Box A : [attachment:A.lhco.gz Events]  Plots:  [attachment:A.pdf Detector level]   ([attachment:A-lhe.pdf Parton level]) 
   * Box B : [attachment:B.lhco.gz Events]   Plots:  [attachment:B.pdf Detector level]   ([attachment:B-lhe.pdf Parton level])  
   * Box C : [attachment:C.lhco.gz Events]  Plots:  [attachment:C.pdf Detector level]   ([attachment:C-lhe.pdf Parton 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.



-- Main.FabioMaltoni - 28 Aug 2008