Bin Number
|
Mean Decay Length (s)
|
Mean Decay Time (s)
|
t (s)
|
1
|
5.25320 E-12
|
5.26699 E-12
|
3.8086 E-13
|
2
|
1.19318 E-11
|
1.19523 E-11
|
6.9891 E-13
|
3
|
1.11187 E-11
|
1.11317 E-11
|
5.3804 E-13
|
4
|
1.15704 E-11
|
1.15802 E-11
|
4.7608 E-13
|
5
|
1.39178 E-11
|
1.39267 E-11
|
4.9883 E-13
|
6
|
1.36513 E-11
|
1.36582 E-11
|
4.3569 E-13
|
7
|
1.69185 E-11
|
1.69254 E-11
|
4.8160 E-13
|
8
|
1.49663 E-11
|
1.49713 E-11
|
3.8846 E-13
|
9
|
1.58498 E-11
|
1.58543 E-11
|
3.7587 E-13
|
10
|
2.00322 E-11
|
2.00369 E-11
|
4.3423 E-13
|
11
|
1.34427 E-11
|
1.34454 E-11
|
2.7074 E-13
|
12
|
1.86430 E-11
|
1.86463 E-11
|
3.4965 E-13
|
13
|
1.89248 E-11
|
1.89277 E-11
|
3.3128 E-13
|
14
|
1.56065 E-11
|
1.56086 E-11
|
2.5604 E-13
|
15
|
2.04128 E-11
|
2.04153 E-11
|
3.2064 E-13
|
16
|
2.51898 E-11
|
2.51925 E-11
|
3.7223 E-13
|
17
|
3.89694 E-11
|
3.89732 E-11
|
5.4373 E-13
|
18
|
2.52780 E-11
|
2.52802 E-11
|
3.3479 E-13
|
|
This should make a bit of sense. All of these events are productions and
decays of the charmed meson. The time between creation and decay of a
particle is called the lifetime. Because the lifetime of a type of
particle is an identifying characteristic, all of these events have that
one thing in common; the lifetime.
What is the average
value of t?
t = 4.1598x10-13 ± 1.1014x10-13
s
This value should look familiar; it is the accepted value for the lifetime
of the charmed meson! Do you recall using it earlier to predict decay
lengths?
Actually the accepted value for the lifetime is
4.15x10-13 ±
0.04x10-13 seconds. The uncertainty in this
number is much better than yours. The most important difference is the
size of the dataset. The accepted value is based on thousands of data
points; your value, only 18. More data yield more precise answers with
smaller uncertainties.
So . . . now
what?
|