Gamma rays are waves, not particles . This means that they have no mass and no charge . Gamma rays have a high penetrating power - it takes a thick sheet of metal such as lead , or concrete to reduce them significantly. Gamma rays do not directly ionise other atoms, although they may cause atoms to emit other particles which will then cause ionisation. Click the button.
Alpha particles are easy to stop, gamma rays are hard to stop.
Particles that ionise other atoms strongly have a low penetrating power , because they lose energy each time they ionise an atom. Radioactive decay is not affected by external conditions. Now let's see how much you've learned. This site is designed to be viewed at 800 x 600 resolution, with level 4 browsers or better.