Mg24

Mg-24, or magnesium-24, is a stable isotope of magnesium with mass number 24. It contains 12 protons and 12 neutrons, and as an even-even nucleus it has spin 0+. Mg-24 is the most abundant magnesium isotope, making up about 79% of natural magnesium; Mg-25 and Mg-26 together account for the remainder. The standard atomic weight of magnesium, reflecting natural isotopic composition, is about 24.305.

In stellar nucleosynthesis, Mg-24 is produced primarily during helium burning, mainly through alpha-capture on neon-20 (the reaction 20Ne(α, γ)24Mg). It can also be formed in later burning stages in massive stars. Its stability and relatively high natural abundance make Mg-24 a convenient reference point in magnesium isotope studies and models of stellar evolution.

Because of its prevalence and stability, Mg-24 is widely used in geochemical and archaeological isotope analyses to calibrate magnesium isotope ratios and to investigate processes such as mineral formation, weathering, and climate proxies. In nuclear physics, Mg-24 serves as a useful target and benchmark in reaction studies due to its simple, doubly even nuclear structure and well-defined properties.