JetEtmissApproved2013HighMuJets
Information Common To All Plots
ρ is calculated using k
t R=0.4 jets reconstructed from
locally calibrated (LCW) topoclusters within |η|<2. The density
calculation is with respect to the Voronoi area of the jets as defined
in
JHEP 0804 (2008) 005. Topoclusters are an attempt to reconstruct three-dimensional
energy deposits in the calorimeter and are built using a
nearest-neighbor algorithm that clusters calorimeter cells with energy
significance (|E
cell|/σ) >4 for the seed, >2 for
neighbors, and >0 at the boundary. E
cell is calibrated
using informaton derived from test beam and detailed GEANT4 simulatons
(EM scale) and σ is the sum in quadrature of the electronic and
expected pileup noise, as described in Sec. 10.5.2 of
JINST 3 (2008) S08003. Topoclusters can be further calibrated using local
information (LCW) as described in
Nucl. Instrum. Meth. A 531 (2004) 481. The pileup noise used in
topoclustering is chosen to match the pileup conditons. Pileup is
simulated by overlaying GEANT4 simulated events from PYTHIA (v6.4)
including non-diffractive and diffractive events.
Truth jets are
built using stable particles from the hard-scatter collision excluding
muons and neutrinos.
A pileup-jet is
defined as a reconstructed jet that is not closely matched in ΔR to a
truth jet. We define a close match as ΔR<0.6, and only truth jets
with p
T >5
GeV are considered.
The mean pileup jet multiplicity as a function of the number of truth
vertices Nvtx in events with an average number of
interactions per bunch crossing (<μ>) of 140. The closed circles (squares) represent the mean number of
pileup jets with pT >20 GeV (solid markers) and 40 GeV
(open markers) before (magenta) and after (blue) pileup subtraction
using the event-by-event median pT density, ρ.
Pileup subtraction significantly reduces the mean number of pileup jets
per event.
|
[pdf]
|
The mean pileup jet multiplicity as a function of the number of truth
vertices Nvtx in events with an average number of
interactions per bunch crossing (<μ>) of 140. The closed circles (squares) represent the mean number of
pileup jets with pT >20 GeV before (magenta) and after (blue) pileup subtraction
using the event-by-event median pT density, ρ.
Pileup subtraction significantly reduces the mean number of pileup jets
per event.
|
[pdf]
|
The mean pileup jet multiplicity as a function of the number of truth
vertices Nvtx in events with an average number of
interactions per bunch crossing (<μ>) of 140. The closed squares (squares) represent the mean number of
pileup jets with pT >40 GeV before (magenta) and after (blue) pileup subtraction
using the event-by-event median pT density, ρ.
Pileup subtraction significantly reduces the mean number of pileup jets
per event.
|
[pdf]
|
Major updates:
--
MichaelBegel - 26-Jul-2013
Responsible:
MichaelBegel
Subject: public