An important absolute dating measure is the decay of 147Sm to 143Nd. What type of radioactive decay is involved in this parent-daughter pair?

The correct answer is alpha decay. 147Sm is a long lived isotope that primarily decays by alpha decay. Alpha decay is a type of radioactive decays at which an atomic nucleus emit an helium nucleus. As a consequence the resultant mass number is reduced by four units and the atomic number is reduced by two units.