sentence: Accelerators sometimes cause nuclear reactions to make radioactive materials.
sentences_before: Nuclear reactions occur in the sun, in nuclear reactors, in particle accelerators, and in outer space. Other than radioactive decay, very few nuclear reactions occur on earth except in these special places. Nuclear reactors use nuclear reactions to make heat and electricity.
sentences_after: Particles from outer space cause nuclear reactions in earth's atmosphere that make air slightly radioactive.
concept_name: accelerator
headings: Nuclear reaction
categories: Nuclear physics