slow neutron

American  

noun

Physics.

1. a neutron with low kinetic energy, especially one slowed by the moderator in a nuclear reactor.

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slow neutron British  

noun

1. physics a neutron having a kinetic energy of less than 100 electronvolts

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slow neutron Scientific  

/ slō /

1. A neutron that is in thermal equilibrium with the surrounding medium, especially one produced by fission in a nuclear reactor, and slowed by a moderator. The uranium 235 used in thermal nuclear reactors undergoes fission more readily when struck by slow neutrons than when struck by the fast neutrons released by fission.

2. Also called thermal neutron

3. Compare fast neutron

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Other Word Forms

• slow-neutron adjective

Etymology

Origin of slow neutron

First recorded in 1930–35

Example Sentences

The rest are thought to originate through slow neutron capture, or the s-process—a relatively well-understood sequence of reactions that occurs in long-lived, low-mass stars.

From Scientific American • Jan. 9, 2023

The slow neutron process was the basis of the early nuclear reactors; without it, there could have been no plutonium.

From Time Magazine Archive

Fermi and Segrè collaborated with three other Italian scientists in perfecting the slow neutron process that was essential to the production of the atomic bomb.

From Time Magazine Archive