An example is the decay of radioactive 4) electron capture also results from an excess of protons.In this type of decay, an electron is spontaneously incorporated into the nucleus and a neutrino is emitted from the nucleus.
These include Os (t½ = 2 x 106 billion years, or 2 million billion years).
The atomic number decreases by one and the neutron number increases by one.
Electron capture may be followed by the emission of a gamma ray.
His Ph D thesis was on isotope ratios in meteorites, including surface exposure dating.
He was employed at Caltech's Division of Geological & Planetary Sciences at the time of writing the first edition.