Isotopes of oxygen
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There are three known stable isotopes of oxygen (8O): 16
O, 17
O, and 18
O.
Radioactive isotopes ranging from 11
O to 28
O have also been characterized, all short-lived. The longest-lived radioisotope is 15
O with a half-life of 122.266(43) s, while the shortest-lived isotope is the unbound 11
O with a half-life of 198(12) yoctoseconds, though half-lives have not been measured for the unbound heavy isotopes 27
O and 28
O.