Tracking Variable Study Follow up Ryan Kelley Boris Mangano Vivek Sharma

p.2 Purpose The purpose of this study is to look at tracking variables in order to determine which tracks are ‘good’ and which are ‘fakes’. Basically, what is a good set of cuts to use (for example isolation studies)?

p.3 Define matched vs. unmatched Loop through all recoTracks in the event and use the RecoToSimAssociator function (associate by hits) in CMSSW to determine if this track is matched to a simulator level particle. If there is no simTrack associated, then it is an unmatched or fake recoTrack.

p.4 Tracking Variables Considered Most Powerful Cut-- hits > 7. SimTrack P T < 1 GeV cut. Don’t understand the two ‘towers’ (Boris believes from increased material).

p.5 Tracking Variables Considered Similar spread for both matched and unmatched. z0 < 30 cm doesn’t really give you anything. Sharp peak between d0 < 1mm. Fakes are very spread.

p.6 Tracking Variables Considered Factor of 10 difference and increasing from  2 > 10.

p.7 Z  (Matched) ~50k Z  events where each recoTrack is matched to a SimTrack.

p.8 Z  (Unmatched) ~50k Z  events where each recoTrack is NOT matched to a SimTrack.

p.9 QCD (Matched) ~120k QCD (50 < pt < 80 GeV) events where each recoTrack is matched to a SimTrack.

p.10 QCD (Unmatched) Need to run on a larger sample

p.11 Ratio of all tracking cuts to no cuts

p.12 Things to do Try reverse matching: Defined unmatched as a SimTrack that doesn’t have a RecoTrack (done). What are the  towers (Boris believes it’s the extra material due to cabling/etc. at  around 1.5). Run on larger samples (done, but should have run on more QCD samples with different pt ranges). Try to cut on expected hits instead of total hits--some of the  regions have more layers than others. A hard number may be not work well the regions with fewer layers.

p.13 Backups Normalized valid hits plot.