2007 CERN Summer student workshop 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 [attachment:h-br.pdf here]. Choose a channel and investigate signal and background: The 4 lepton final state: $pp \to H\to Z Z \to e^+e^- \mu^+ \mu^-$ Signal Events: [attachment:h4l-signal.lhe.gz Parton Level] [attachment:h4l-signal.lhco.gz Detector Level] Plots: [attachment:h4l-signal-lhe.pdf Parton Level] [attachment:h4l-signal-lhco.pdf Detector Level] Background Events: [attachment:h4l.lhe.gz Parton Level] [attachment:h4l.lhco.gz Detector Level] Plots: [attachment:h4l-lhe.pdf Parton Level] [attachment:h4l-lhco.pdf Detector Level] The 2 lepton + missing Et final state: $pp \to H\to W^+ W^- \to e^- \bar \nu_e \mu^+ \nu_\mu $ Signal Events: [attachment:hww-signal.lhe.gz Parton Level] [attachment:hww-signal.lhco.gz Detector Level] Plots: [attachment:hww-signal-lhe.pdf Parton Level] [attachment:hww-signal-lhco.pdf Detector Level] Background Events: [attachment:hww-background.lhe.gz Parton Level] [attachment:h4l-background.lhco.gz Detector Level] Plots: [attachment:h4l-background-lhe.pdf Parton Level] [attachment:h4l-background-lhco.pdf Detector Level] Top associated production $pp \to t\bar tH$ with $H \to b \bar b$ Signal + Background samples: Events: [attachment:ttbb.lhe.gz Parton Level] [attachment:ttbb.lhco.gz Detector Level] Plots: [attachment:ttbb-lhe.pdf Parton Level] [attachment: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 : [attachment:A.lhco.gz Events] Plots: [attachment:A-lhe.pdf Parton level] [attachment:A.pdf Detector level] Box B : [attachment:B.lhco.gz Events] Plots: [attachment:B-lhe.pdf Parton level] [attachment:B.pdf Detector level] Box C : [attachment:C.lhco.gz Events] Plots: [attachment:C-lhe.pdf Parton lelve] [attachment: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. -- Main.FabioMaltoni - 08 Aug 2007 2012 CERN Summer student workshop 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 [attachment:h-br.pdf here]. Choose a channel and investigate signal and background: The 4 lepton final state: $pp \to H\to Z Z \to e^+e^- \mu^+ \mu^-$ Signal Events:: [attachment:h4l-signal.lhe.gz Parton Level] [attachment:h4l-signal.lhco.gz Detector Level] Plots:: [attachment:h4l-signal-lhe.pdf Parton Level] [attachment:h4l-signal-lhco.pdf Detector Level] Background Events:: [attachment:h4l.lhe.gz Parton Level] [attachment:h4l.lhco.gz Detector Level] Plots: [attachment:h4l-lhe.pdf Parton Level] [attachment:h4l-lhco.pdf Detector Level] The 2 lepton + missing Et final state:: $pp \to H\to W^+ W^- \to e^- \bar \nu_e \mu^+ \nu_\mu $ Signal Events:: [attachment:hww-signal.lhe.gz Parton Level] [attachment:hww-signal.lhco.gz Detector Level] Plots:: [attachment:hww-signal-lhe.pdf Parton Level] [attachment:hww-signal-lhco.pdf Detector Level] Background Events:: [attachment:hww-background.lhe.gz Parton Level] [attachment:h4l-background.lhco.gz Detector Level] Plots:: [attachment:h4l-background-lhe.pdf Parton Level] [attachment:h4l-background-lhco.pdf Detector Level] Top associated production $pp \to t\bar tH$ with $H \to b \bar b$ Signal + Background samples: Events:: [attachment:ttbb.lhe.gz Parton Level] [attachment:ttbb.lhco.gz Detector Level] Plots:: [attachment:ttbb-lhe.pdf Parton Level] [attachment: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 : [attachment:A.lhco.gz Events] Plots: [attachment:A-lhe.pdf Parton level] [attachment:A.pdf Detector level] Box B : [attachment:B.lhco.gz Events] Plots: [attachment:B-lhe.pdf Parton level] [attachment:B.pdf Detector level] Box C : [attachment:C.lhco.gz Events] Plots: [attachment:C-lhe.pdf Parton lelve] [attachment: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. -- Main.FabioMaltoni - 08 Aug 2007 -- Main.FabioMaltoni - 2011-07-12