Isotopes of oxygen
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There are three known stable isotopes of oxygen (8O): 16
O, 17
O, and 18
O. Radioisotopes are known from 11O to 28O (particle-bound from mass number 13 to 24), and the most stable are 15
O with half-life 122.27 seconds and 14
O with half-life 70.62 seconds. All remaining radioisotopes are even shorter in lifetime. The four heaviest known isotopes (up to 28
O) decay by neutron emission to 24
O, whose half-life is 77 milliseconds; 24O, along with 28Ne, have been used in the model of reactions in the crust of neutron stars. The most common decay mode for isotopes lighter than the stable isotopes is β+ decay to nitrogen, and the most common mode after is β− decay to fluorine.