COT Simulation Validation Plots

current release	next release	description
eps file	eps file test eps file	Hit Resolution (Data versus Simulation) The default GARFIELD parameter controlling the hit resolution has been scaled by 0.4 to match the observed hit resolution. Hits over the entire cell are included in this plot. Tracks used are COT-only.
eps file	eps file	Hit Resolution (Data versus Simulation) Same as above but hits with drift distance between 2 and 7 mm only are included in these plots. Tracks used are COT-only.
eps file	need MC comparison	D0 Distribution from W Muons COT-only tracks - need MC comparison
eps file	need MC comparison	D0 Pull Distribution from W Muons COT-only tracks - need MC comparison
eps file	good as is (but need to check effect of multiple interactions at higher luminosity)	Primary Track Spectrum in COT Primary COT tracks are selected with |d0| < 3 mm and at least 24 axial and 24 stereo COT hits. The per-event spectrum of charge-signed 1/Pt shows that the simulation models the primary track multiplicity well (given that Rick Field's Pythia tune is used here). The data were taken at low luminosity and no additional interactions were simulated. The comparison validates the W underlying event modelling (from the tracking point of view).
eps file	ready to go	Primary COT Track Multiplicity Same as above but showing the track multiplicity per event, modelled well by the simulation.
eps file	open issue - need to address	Good COT Track Spectrum The impact parameter cut from above is removed, allowing secondary tracks. The excess in the data, and the charge asymmetry, may suggest that secondary interactions are under-estimated in GHEISHA. FLUKA gives similar results to GHEISHA. The possibility that the MC deficit is all due to missing passive material is largely excluded by the fact that the muon dE/dx measurements (using J/psi fits and cosmic rays) are consistent with the simulation geometry within 5% or so. Since dE/dx scales with electron density and interaction lengths scale with nucleon density, the two are proportional for constant neutron/proton ratio. As there is some missing copper in the simulation geometry, and copper has 10% excess nucleons/electron as compared to low Z materials, a part of the MC deficit can be attributed to this.
eps file	open issue - need to address	Good COT Track Multiplicity Same as above, showing fewer COT tracks in simulation than data.
eps file	open issue - need to address	Spectrum of All Tracks COT hit requirements from above are removed, allowing also silicon standalone tracks. The deficit in the simulation gets worse. Updates to the simulation geometry to include the missing copper (based on studies of photon conversions) will allow for a better comparison. Direct mapping of secondary hadronic interactions using reconstructed secondary vertices will also be very useful.
eps file	open issue - need to address	Multiplicity of All Tracks COT hit requirements from above are removed, allowing also silicon standalone tracks. The deficit in the simulation gets worse.
eps file	eps file	Hit Width Hits with width<10 ns removed. Tail in the data at high width may be due to merged hits in the inner superlayers, due to higher occupancy (see plots above).
eps file	nothing new	Mean Number of COT Hits per Superlayer on Muon Hits on inner superlayers may be obscured in the data due to higher occupancy than the simulation.
eps file	nothing new	Total Number of COT Hits on Muon Track Consequence of above.
data ps file MC ps file	nothing new	Distribution of COT Hits per Superlayer on Muon Track
eps file	eps file	Dimuon Z Mass (plot from Victoria Martin)
eps file	eps file	Dimuon Z Pt (plot from Victoria Martin)

Other related web pages:

• Tracking.

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