Radioactive dating after 2 half lives
Beta (β) decay is the emission of an electron from a nucleus.
Iodine-131 is an example of a nuclide that undergoes β decay: Beta decay, which can be thought of as the conversion of a neutron into a proton and a β particle, is observed in nuclides with a large n:p ratio.
Following the somewhat serendipitous discovery of radioactivity by Becquerel, many prominent scientists began to investigate this new, intriguing phenomenon.
Among them were Marie Curie (the first woman to win a Nobel Prize, and the only person to win two Nobel Prizes in different sciences—chemistry and physics), who was the first to coin the term “radioactivity,” and Ernest Rutherford (of gold foil experiment fame), who investigated and named three of the most common types of radiation.
Cobalt-60 emits γ radiation and is used in many applications including cancer treatment: Positron emission is observed for nuclides in which the n:p ratio is low. Positron decay is the conversion of a proton into a neutron with the emission of a positron.
(credit a: modification of work by Jens Maus)O () and incorporated into a glucose analog called fludeoxyglucose (FDG).Ernest Rutherford’s experiments involving the interaction of radiation with a magnetic or electric field (Figure 2) helped him determine that one type of radiation consisted of positively charged and relatively massive α particles; a second type was made up of negatively charged and much less massive β particles; and a third was uncharged electromagnetic waves, γ rays.We now know that α particles are high-energy helium nuclei, β particles are high-energy electrons, and γ radiation compose high-energy electromagnetic radiation.Electron capture occurs when one of the inner electrons in an atom is captured by the atom’s nucleus.For example, potassium-40 undergoes electron capture: Electron capture occurs when an inner shell electron combines with a proton and is converted into a neutron.