What is the source size of an XRF instrument?

The source size of an XRF (X-ray fluorescence) instrument is measured in terms of radioactivity, and the unit that best fits this context is the milliecurie (mCi). The milliecurie is a standard unit used to measure the activity of radioactive material, indicating how many disintegrations occur per second.

In XRF instruments, radioactive sources are often calibrated in curies (Ci) or its subunits like milliecuries, which serve to quantify the strength of the radioactive source used in generating X-ray fluorescence. This measurement is critical for assessing the intensity of radiation emitted and thus the quality and reliability of analysis.

Contrastingly, metrics like microsievert (µSv) and bequerel (Bq) are primarily used to measure the dose of radiation received by a person or the activity of a radioactive source respectively, making them less relevant for evaluating the source size in terms of XRF instrument specifications. The curie (Ci) may also be relevant as it denotes the total radioactivity, but for practical applications in XRF instruments, the milliecurie is more commonly utilized as it provides a more manageable scale for source size.