Hajoamiskäyrä

Hajoamiskäyrä refers to a graphical representation illustrating the decay of a radioactive substance over time. The y-axis typically represents the quantity of the radioactive material, which could be its mass, number of atoms, or activity (number of decays per unit time). The x-axis represents time. The curve starts at its maximum initial quantity and decreases as the radioactive nuclei undergo decay.

The characteristic shape of a hajoamiskäyrä is exponential, meaning that in any given time interval, a fixed fraction of the remaining radioactive material will decay. This decay rate is constant for a specific isotope and is quantified by its half-life. The half-life is the time it takes for half of the initial amount of the radioactive substance to decay. On the graph, this corresponds to the time at which the curve reaches half of its initial y-value.

Each radioactive isotope has a unique half-life, and consequently, a unique hajoamiskäyrä. This property makes radioactive decay useful in various applications, such as radiometric dating, where the age of geological samples or artifacts can be determined by measuring the ratio of parent isotopes to their decay products. The decrease in radioactivity over time is predictable and follows this characteristic curve.