What are the three major radiations experienced by heavy unstable nuclei, and how does the penetrating power compare for each?

α - Emission of a Helium nucleus, it has the highest mass and lowest energy of the three types of radiation, it has a +2 overall charge due to its 2 neutron - 2 proton makeup, and can penetrate up to a few sheets of paper only. β - Emission is release of a fast moving electron via the decay of a neutron into a proton within the atom, it can penetrate much farther than an alpha particle and will be stopped by a layer of Aluminium foil.Gamma emission is the release of an electromagnetic wave with the highest penetrating power and no relative mass, gamma rays will only be stopped by heavy shielding such as lead or thick concrete.