Systematics studies - Hadronic energy flow

1
Systematics studies - Hadronic energy
flow R.Goncalo
Question How well does the Monte Carlo describe
the hadronisation? (Double angle relies on good
reconstruction of ?H) Method Define the Hadronic
energy flow average energy deposit per event in
islands, calculated in bins of polar
angle Islands remaining after CorAndCut
energy correction and backsplash cut. Cells
corresponding to the electron were discarded
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Systematics studies - Hadronic energy flow
BCAL
BCAL
BCAL
FCAL
FCAL
FCAL
BCAL
BCAL
RCAL
FCAL
RCAL
BCAL
BCAL
BCAL
RCAL
RCAL
RCAL
BCAL
BCAL
?Ariadne (CorAndCut) seem to describe the data
well to first approximation Lepto (MEPS) a bit
worse
current jet
current jet
Proton remnant
BUT...
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Systematics studies - Hadronic energy flow
Superposition of current jet and remnant
1st IR
beampipe
Now plotting dE/dRFCAL
Energy flow in FCAL 10 cm radial bins
remnant
Jet in BCAL
? Ariadne not good in 1st IR MEPS closer to data
but still not perfect
jet
Jet in BCAL
Jet in BCAL
Jet in BCAL
Jet in BCAL
Jet in BCAL
Jet in BCAL
4
Systematics studies - Hadronic energy flow

• The problem divided itself into
• 1st Inner Ring (remnant/very low y)
• Hadronisation of the current jet
• 1) First inner ring
• Tried varying
• Intrinsic KT of proton (0.01-1.66 GeV, default
  0.45 GeV)
• KT of proton remnant (0.05-0.8 GeV, default 0.35
  GeV)
• No clear improvement, small local changes only.
• Will find some way of quantifying systematic
  error for 1st IR.
• 2) Hadronisation
• Does the difference Ariadne/MEPS quantify our
  ignorance?

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Systematics studies - Hadronic energy flow