Particle physics – Physics Academy London

CAIE
11. Particle physics

infer from the results of the α-particle scattering experiment the existence and small size of the nucleus
describe a simple model for the nuclear atom to include protons, neutrons and orbital electrons
distinguish between nucleon number and proton number
understand that isotopes are forms of the same element with different numbers of neutrons in their nuclei
understand and use the notation A ZX for the representation of nuclides
understand that nucleon number and charge are conserved in nuclear processes
describe the composition, mass and charge of α-, β- and γ-radiations (both β– (electrons) and β+ (positrons) are included)
understand that an antiparticle has the same mass but opposite charge to the corresponding particle, and that a positron is the antiparticle of an electron
state that (electron) antineutrinos are produced during β– decay and (electron) neutrinos are produced during β+ decay
state that (electron) aunderstand that α-particles have discrete energies but that β-particles have a continuous range of energies because (anti)neutrinos are emitted in β-decayntineutrinos are produced during β– decay and (electron) neutrinos are produced during β+ decay
represent α- and β-decay by a radioactive decay equation of the form U Th 92 238 90 234 2 " + 4α
use the unified atomic mass unit (u) as a unit of mass

understand that a quark is a fundamental particle and that there are six flavours (types) of quark: up, down, strange, charm, top and bottom
recall and use the charge of each flavour of quark and understand that its respective antiquark has the opposite charge (no knowledge of any other properties of quarks is required)
recall that protons and neutrons are not fundamental particles and describe protons and neutrons in terms of their quark composition
understand that a hadron may be either a baryon (consisting of three quarks) or a meson (consisting of one quark and one antiquark)
describe the changes to quark composition that take place during β– and β+ decay
recall that electrons and neutrinos are fundamental particles called leptons