Analyzing data from a real ALEPH event

by Wolfgang Pils    (with a lot of help and suggestions from Guenther Dissertori ) 

The aim of this interactive tutorial is to give you a (simplified) idea how real data from the ALEPH detector at the Large Electron Positron collider (LEP)  can be analyzed using only high school physics, geometry and mathematics. 

Each of the chapters can be done (more or less) independently to the others. 

Previous knowledge

Here you find a short summary of the physics you should be familiar with before you are going through the different chapters.. 

The ALEPH detector

Here you find a very short explanation of the ALEPH experiment.

A kaon travels too far

This is a short exercise showing that relativity is not just a theory: In high energy collisions, it comes in every day.

Tracking with simple geometry

To calculate the momentum of a charged particle you have to know the radius of its curved track. In this exercise you learn how to calculate this radius, knowing only three equidistant points on the track.

Calculating the momentum and energy from the track radius

In this part you will learn how to calculate the momentum and energy of a particle once you know the radius of its trajectory.

What really happened?

In the previous chapters we identified all the emerging particles. Now the more challenging question: what happened right after the electron positron collision? We will try to guess what happened.

Why are these detectors so huge?

This simple exercise will show you that you need strong magnetic fields and large chambers to detect high energy particles like muons.

Solutions to the exercises

Worked answers to all the questions.

Links 

other pages where you can learn how to analyze data of actual experiments