sentence2_structure: A neutron<>collides<>with an atom of u-235 during the basic nuclear fission process
sentence1: Nuclear fission can occur without neutron bombardment as a type of radioactive decay.
sentence2: A neutron collides with an atom of u-235 during the basic nuclear fission process.
question: What type of particle collides with an atom of u-235 during the basic nuclear fission process?