Date: 5 April 2025
Tag: sPH-CONF-JET-2025-04
Document: Conference Note
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Figure 1 
An example of the fit to the formula in Equation 3 for 0-2% central events. The x-axis is scaled by the area of a single tower and the points represent calorimeter-window areas with dimensions presented in Table 1. |
Figure 2 
The correlation parameter k from Equation 3 for all fits to the dependence of the mean standard deviation in calorimeter window transverse energy at electromagnetic scale to calorimeter window area, as a function of event centrality. Statistical uncertainties are included. The shaded boxes are the systematic uncertainty from varying the range of fitted window area. |
Figure 3 
δETRaw distributions for random cones reconstructed in 0-5% central events for area-based subtracted (red), multiplicity subtracted (blue), and iteratively subtracted (green) data. The left plot is calculated using random cones constructed with towers in their nominal positions, while the right uses random cones constructed with towers which have had their η and φ positions randomized. Values for μ and σ are given in GeV and correspond to the mean and R.M.S of the given distribution. |
Figure 4 
Comparisons of the estimated underlying event distributions for an R=0.4 cone using the multiplicity-based method (open), and the area method (closed) measured in Au+Au events. |
Figure 5 
δET for multiplicity subtracted (top left), iteratively subtracted (top right), and area subtracted (bottom) underlying-event characterizations in 0-5% central Au+Au events at √sNN = 200 GeV for random cones in minimum bias data, both with and without randomizing the tower positions, and in minimum bias data with high-ET probes and jets embedded in the event. Values for μ and σ are given in GeV and correspond to the mean and R.M.S of the given distribution. |
Figure 6 
Centrality dependence of σ(δET) of both types of random cones for all background subtraction methods, compared to the Poissonian limit calculated with measured ET,Tower and to that plus additional hydrodynamic flow contributions calculated with elliptical flow v2 measured in [23] and triangular flow measured in [24]. The solid black line corresponds to the Poissonian limit given by Eq. [5]. The dotted and dashed black lines correspond to estimations of the Poissonian (σP) and non-stochastic (σNS) contributions given by Eq. [7] and Eq. [8], respectively. |
Figure 7 
Ratio of σ(δET) to stochastic fluctuations σP given by Eq. [5]. The fractional contributions to underlying event fluctuations σ(δET) for random cones subtracted with each background subtraction method are shown via Eq. [6]. The Poisson (statistical) limit is used as a scale. |
Figure 8 
δET distributions for jets reconstructed in events with ET,probe = 30 GeV probe (left) embedded PYTHIA event (right). Both panels are for 0-5% central events and show the results of the area-based subtracted (red), multiplicity subtracted (blue), and iteratively subtracted (green) jets. |
Auxiliary Figures 
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