W-Path
First, let's find out how to identify elementary particles. Next, you can actually work with real ATLAS data from the Large Hadron Collider (LHC) at CERN. In the process you have to do a bit of detective work because at a proton-proton collision – a so-called "event" – a lot of particles are generated. The key task is to search the results for specific elementary particles and to assign them to physical processes. In doing so you get to know the challenges physicists have to face.


To begin the W-path, the animation below will draw your attention to the main actor – the W particle. This plays an important role in radioactive decay, as is shown with the example of Potassium-40. Potassium-40 is an unstable isotope with 40 nucleons (19 protons and 21 neutrons) in the nucleus and decays by emission of a negative or positive beta particle. We have chosen potassium as an illustration because it is essential for the human body and is responsible for the water content in our cells. It is also an important electrolyte in body fluids. About every 9000th potassium atom of the approximately 100 grams of potassium in your body is potassium-40. Our animation shows how particle physicists see the beta decay which occurs in your body:


Tim Hermann, Konrad Jende, CERN, July 2010

You can find further details about this decay here.