dating methods, AMS requires smaller sample sizes (about 50 mg), while yielding extensive chronologies. MS technology has expanded the scope of radiocarbon dating. Samples ranging from 50,000 years old to 100 years old can be successfully dated through utilizing AMS. An accelerator mass spectrometer is required over other forms of mass spectrometry due to their insufficient suppression of molecular isobars to resolve 13CH and 12CH2 from radiocarbon. Because of the long half-life of 14C decay counting requires significantly larger samples. 10Be, 26Al, and 36Cl are used for surface exposure dating in geology. 3H, 14C, 36Cl, and 129I are used as hydrological tracers. Accelerator mass spectrometry is widely used in biomedical research. In particular, 41Ca has been used to measure bone resorption in postmenopausal women. See also List of accelerator mass spectrometry facilities Arizona Accelerator Mass Spectrometry Laboratory References Bibliography Mass spectrometry