Pre-Lab Questions to Lab 12 - Elementary Particles On the world-wide-web or in your favorite textbook look up the rest mass in units of MeV/c2 of the following particles: electron, positron, proton, neutron, deuteron, $\alpha$-particle, muon ($\mu$+ or $\mu$-), charged pion ($\pi$+ or $\pi$-), neutral pion ($\pi$o), W+, W-, Zo, charm-quark, bottom-quark, and the top-quark. The top quark is the most massive of the six quarks. Express its rest mass in atomic mass units and compare it to the elements in the periodic table, i.e. which element comes closest to the mass of the top quark? A charged particle in a magnetic field moves on a curved trajectory; once the track is recorded in the drift chamber the momentum of the particle is determined from the curvature of the particle track. Show how you find the radius of curvature of an 50 GeV/c electron moving perpendicular to field of 0.5 T. (You may want to check out the Java applet at http://www.phy.ntnu.edu.tw/java/emField/emField.html )