Jet substructure analysis is an important tool for extractions of the significant signal in jets and the reconstruction of characteristic jet mass and shape variables, and the e.g. internal flow inside jets, for e.g. searches. This project tries to evaluate various substructure techniques and configurations with respect to their effectiveness in the suppression of pile-up for given observables, and the enhancement of signal-to-background ratios.

While the exact conditions at LHC are not yet know, we expect at least 30 but likely more (more than 200 is possible) pile-up interactions in each recorded event. The center-of-mass energy is set to $ \sqrt{s} = 13 {\rm\ TeV} $. }

Minimum bias samples have been produced with Pythia8 using the tune 4C. The samples include single, double and non-diffractive interactions at the default mix. Particles are generated without any phase space restriction. The generating code fills a ROOT tuple, the structure of which is documented in the BOOST2012 TWiki.

The generating code can be found in the file pythiasoftqcdall.cc.txt. The example Makefile is in the file makefile.txt. This is highly taylored for the setup on my machine, but should give you an idea.

The following signal samples were discussed:

1. Final states with boosted objects:
   1. _signal_ : boosted top in $t\bar{t}$ ($\hat{p}_{T} > 200(450) {\rm\ GeV}$); full hadronic ok;
   2. _background_ : inclusive jets in similar phase space as $t\bar{t}$;
2. VBS/VBF with (not boosted) tag jets
   1. WW/ZZ/WZ continuum, high $M_{WW/ZZ/WZ} > 1 {\rm\ TeV}$ (may be not possible in Pythia8 - maybe have to go for a high mass Higgs-like particle?)
   2. VBF Higgs $H(125)$, $H\to\gamma\gamma$