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Figure 9. Second Logic circuit layout. of muons detected in both scintillators diminished.
This was to be expected, as the more separated
For a fixed separation of two detectors, the signal the detectors are, the smaller is the solid angle
from the upper one (converted to a logic pulse) subtended by the areas of the scintillators, and
was used as the START of the TAC, while the signal therefore, the amount of muons that actually go
of the lower PMT was first introduced to a Gate and through both scintillators is less. A consequence of
Delay generator, where it was delayed a known this, is that the experimental setup needed to run
amount of time, and then it was used as the STOP for longer times as the separations increased in
for the TAC. The MCA registered the amplitude of order to get a time distribution of the same order as
the TAC in a specific channel or bin for each delay. for the smaller separations.
A curve fit was then made to find the relation
between the histogram bins and the actual time Table 1. Operation times.
separation of the pulses. The calibration curve is
shown in fig. (10).
Distance (meters) Time (days)
0.5 6
1 8
After enough measurements with each
separation
distance, a distribution of the time intervals was
obtained. A curve fit was then carried out to find
the mean value of the time interval for each
distance, which is given as the sum of the time for
the muon to go from one detector to the other, plus
the delay. This mean values for the time intervals for
Figure 10. MCA Calibration. each separation (eq. (9) and eq. (10)), were then
used to calculate the mean velocity of the
B3. Operation detected muons according to eq (12).
Time measurements were made for two different
separation distances of the scintillators: 0.5m and
1m. As the separation was increased, the amount
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Año 10 Núm. 30 septiembre-diciembre 2024 Tlahuizcalli ISSN: 2448-7260