Probing the Protons
Probing the Protons
We start with a description of cosmic rays and gamma rays. They collide with atoms in the atmosphere to create a wide variety of particles. We cover how cloud chambers work to ‘see’ these new particles. That includes taking a look at the tracks for electrons and protons. We then take a look at the new particles we found on mountain tops and up in balloons: positrons, electron-positron pair creation, muons; pions; kaons; and particle decay timing and signatures.
We then cover the hard-to-find neutrino, starting with the Ellis – Wooster experiment to measure the energy of radium decay into polonium that led to Wolfgang Pauli’s 1927 prediction about the existence of the neutrino. We then take a look at the 1970 bubble chamber track that first detected it.
Next, we probe the proton using scattering experiments like the ones used by Rutherford to probe the nucleus. This time we use electrons instead of alpha particles. We cover how this was done at the Stanford Linear Accelerator Center (SLAC) in 1969. We show how particle acceleration is accomplished, and how particle detection is done with hodoscopes and calorimeters. We also examine the test results, explaining the idea of ‘cross section’ measurements as a way to identify scattering target sizes. We end with the results that showed that the proton has 3 parts: now called quarks.
