Nuclide identification, mass

The development of mass spectrometric techniques for nuclide identification using a tandem Van de Graaff accelerator at the University of Rochester Nuclear Structure Laboratory by H. Gove, K. Purser, A. Litherland, and numerous associates has provided an excellent means for the precise measurement of 36C1 concentrations in natural water [43]. Thus far, about 40 groundwater related samples which have been collected and purified chemically by H. Bentley have been analyzed for 36C1 by D. Elmore, H. Bentley, and others using the University of Rochester machine. Some of these samples are listed in Table 2. 

The various kinds of atoms differing from each other by their atomic number or by their mass are called nuclides. The correct name of unstable (radioactive) nuclides is radionuclides, and the terms radioelements for unstable elements and radionuclides for unstable nuchdes are analogous. For identification, the symbol (or the atomic number) and the mass number are used. For example, is carbon with the mass number 14 and the atomic number 6. The atomic munber can be omitted ( " C), because it is known by the symbol. can also be written as C-14. For complete information, the kind and the energy of transmutation and the half-life may also be indicated ... 

Masses measured with a few parts per million (ppm) accuracy can provide an unequivocal identification of the atomic composition. This is due to the fact that the atomic weights of the nuclides are not exact whole numbers on the C mass scale (e.g., H = 1.007825, = 15.99491, = 14.00307, = 31.97207). Accurate mass measurements are most... 

---