Samarium-149
/səˈmɛəriəm wʌn ˈfɔːr ˈnaɪn/noun
A naturally occurring radioactive isotope of samarium containing 62 protons and 87 neutrons.
Did you know?Samarium-149 is a powerful neutron absorber and can build up in nuclear fuel, influencing reactor reactivity as a so-called fission product poison.
Etymological Timeline
19th Century
Russian
Samarsky
“Surname of Vasili Samarsky-Bykhovets, a Russian mining official whose name became attached to the mineral samarskite.”
1847
Russian/French
samarskite
“A mineral named after Samarsky; it was later recognized as a source of several rare-earth elements.”
1879
French
samarium
“Chemical element named for samarskite, honoring the surname Samarsky.”
Late 19th Century
Scientific English
samarium
“The English name for the rare-earth chemical element with atomic number 62.”
20th Century
Nuclear physics
samarium-149
“The isotope designation identifying samarium with mass number 149: 62 protons plus 87 neutrons.”
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