10 - H1 - Desy

5.3 Exclusive selection and its subselections 69
Events
500
400
300
Sum MC
Signal
Background
Events
500
a. b.
400
300
200
200
100
100
0
-1 -0.5 0 0.5 1 1.5 2 2.5
jet
η
0
5 10 15 20
[GeV]
jet
E T
Figure 5.6: The distribution of the pseudorapidity η jet (a) and transverse energy E jet
T
(b) of the leading hadronic jet plotted together with the MC prediction. The vertical lines
indicate the cut values.
In addition, the exclusive sample was divided into two subsamples based on the x LO
γ
variable defined with equation 1.41. The estimator of x γ is used to divide the phase
space into parts with enhanced direct contribution (x LO
γ > 0.8) and enhanced resolved
contribution (x LO
γ < 0.8). Figure 5.7 presents the x LO
γ and parallel x LO
p distributions
together with MC predictions and the cut value separating the two subsamples. One
can estimate that roughly 80% of all the signal events in the direct enhanced sample
actually comes from genuinely direct events. Resolved and radiated events contribute to
the resolved enhanced sample on the level of 53% and 30% respectively.
Events
500
450
400
350
300
250
200
150
100
50
resolved
enhanced
direct
enhanced
0
0 0.2 0.4 0.6 0.8 1 1.2
LO
x γ
Events
600
a. b.
500
400
300
200
100
Sum MC
Resolved+Radiated
Direct
Background
0
0 0.02 0.04 0.06 0.08 0.1
LO
x p
Figure 5.7: The distribution of the x LO
γ (a) and x LO
p (b) estimators. The data points
are plotter together with the MC prediction. The vertical line in the x LO
γ distribution
indicates the chosen cut value separating direct and resolved enhanced phase spaces.
The effect to be studied in direct and resolved enhanced subsamples is the correlation
between hadronic jet and a photon candidate. Two variables defined in the section 1.5,
∆Φ and p ⊥ are studied and their distributions are presented in figure 5.8.