carbon 13

American  

Also carbon-13

noun

1. the stable isotope of carbon having an atomic mass number 13, used as a tracer.

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Etymology

Origin of carbon 13

First recorded in 1940–45

Example Sentences

Recent separate findings indicate that plant leaves receiving more light have a higher density of veins, as well as a higher ratio of a naturally occurring isotope called carbon 13.

From Scientific American • Apr. 1, 2021

There’s carbon 12 and its ever-so-slightly-heavier sibling, carbon 13.

From Washington Times • Jun. 11, 2017

They found that the amount of carbon 12, the isotope most utilized in biological processes, was high in relation to carbon 13.

From Time Magazine Archive

Besides the various amino acids, Ponnamperuma's team detected a greater proportion of carbon 13 than would be present in earthly organic matter.

From Time Magazine Archive