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n. An electrically neutral subatomic particle in the baryon family, having a mass 1,839 times that of the electron, stable when bound in an atomic nucleus, and having a mean lifetime of approximately 1.0 × 103 seconds as a free particle. It and the proton form nearly the entire mass of atomic nuclei. See Table at subatomic particle.

n. A subatomic particle forming part of the nucleus of an atom and having no charge; it is a combination of an up quark and two down quarks

n. an elementary particle with 0 charge and mass about equal to a proton; enters into the structure of the atomic nucleus

"Cosmo – A long-term neutron measurement project, under the tutelage of the late Dr. Jack Lockwood and Dr. Jim Ryan of UNH's Physics Department, Institute for the Study of Earth, Oceans, and Space."

nucleon   

proton    electron   

neutron bomb   

X-ray    proton    neutrino    electron    gamma    ultraviolet    photon    tachyon    x-rays    microwave