LATE 1940s at the University of Chicago by Willard LIBBY, who received the Nobel Prize in Chemistry for his work in 1960. It is BASED on the fact that radiocarbon (14C) is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen.The resulting \({}_{}^{14}C\) combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire 14C by eating the plants. In 2020, the Nobel prize for chemistry won by Emmanuelle Charpentier and Jennifer A. Doudna for the development of a method for genome editing.Carbon - 14 is an isotopic chronometer.There are three principal techniques used to MEASURE carbon 14 content of any given sample— gas proportional counting, liquid scintillation counting, and accelerator mass spectrometry.