The aim of the bubble chamber picture data processing system is
to produce well-measured values for the energy and momentum of each
particle produced in a collision. For our event this is contained
in the following record.
The details are very complicated technically, so here we will limit
ourselves to listing some of the key ideas:
- The aim of the bubble chamber picture data processing system
is to produce well-measured values for the energy and momentum
of each particle produced in a collision. For our event this is
contained in the following record.
The details are very complicated technically, so here we will
limit ourselves to listing some of the key ideas:
By means of a computer controlled measuring device, the coordinates
of vertices and points on tracks are determined on three views
and stored
- Using the accurately-known positions of 'fiducial' crosses
scratched onto the bubble chamber windows, the measured coordinates
are used to calculate the curves along which the particles have
traveled. Having made corrections to allow for the fact that the
particles are slowing down, the curves are used to calculate the
energy and momenta of the particles as they leave the collision
point.
(Due to measurement errors, it is not always possible to do this
in a unique way.)
for our event the following unique assignment was possible:
| |
px (MeV/c) |
py (MeV/c) |
pz (MeV/c) |
E (MeV/c) |
| K |
8213.4 |
-248.3 |
15.2 |
8232.0 |
| p |
0.0 |
0.0 |
0.0 |
938.3 |
| |
|
|
|
|
| K- |
1481.8 |
27.8 |
224.0 |
1578.1 |
| pi- |
149.7 |
-11.3 |
38.8 |
208.6 |
| pi+ |
37.9 |
-122.2 |
-22.7 |
190.7 |
| p |
1508.6 |
128.5 |
-70.5 |
1782.6 |
| K0 |
3545.6 |
-162.9 |
-245.0 |
3592.4 |
What is the purpose of data processing?
It is to provide as full a record as possible of all the interactions
found in an experiment - which typically might have tens or even
hundreds of thousands of interactions.
These are then analyzed by programs written by physicists to compare
the results of the experiment with current theoretical ideas.
|