Etude et impact du bruit de fond corrélé pour la mesure de l'angle ...

Figure 7.1: Distribution of RMS(Tstart) for physics events.
84 4. Measurement of ✓ 13 with the Double Chooz far detector
tel-00821629, version 1 - 11 May 2013
(a) Prompt
(b) Delayed
Figure Figure 7.2: 4.5: Distribution Q max /Qof tot MQTQ for prompt variable. (left) The distribution and delayed is shown [6, 12] for MeV neutrino (right) candidates
candidate. (black) and On accidentals time selection (red) in the with prompt t in (left) [2, and 100] delayed µs is(right) shownenergy withwindows.
black
points. O↵ time selection with t in [1, 100] ms (rescaled to on time window
width) is shown with red histogram.
Entries/2µs
Prompt-delay time difference
2
10
anti-
Data
MC
Double Chooz Preliminary
129
Distance
Entries/2cm
3
10
2
10
10
1
-1
10
anti-
Data
MC
Double Chooz Preliminary
10
0 20 40 60 80 100
T (µs)
-2
10
0 50 100 150 200
Distance (cm)
Figure 4.6: Time (left) and spatial (right) correlation between prompt and
delayed events. Both data (black points) and ¯⌫ e MC (yellow histograms) are
shown. The time correlation shows the fast neutron thermalization time, of
the order of ⇠ 5 µs, and the slower neutron-Gd capture time, of the order
of ⇠ 30 µs. The spatial distribution shows correlation up to ⇠ 1.5 m and
a flat uncorrelated component above ⇠ 1.5 m, most likely due to accidental
background contamination.