A neutron source is a device that emits neutrons, used in particle physics and to start of nuclear chain reactions. Usually, the neutron souce is high speed atoms hitting a metal of an isotope with many neutrons. This reaction can be seen as bright sparks, but the sparks each have many neutrons in them.
... and Mary[?] at Louvain, and was admitted to the religious profession on October 7, 1860. Three years later he was sent to Hawaii, where he was ordained on May 24, 1864. ...