Tandem Van de Graaff

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. 

Figure 14.6 Two-stage tandem Van de Graaff accelerator. [From R. J. Van de Graaff, Nucl. Instr. Meth. 8, 195 (I960).]...

The equipment required to perform NRA and ERD is very similar. A particle accelerator (e.g., Van de Graaff or Tandem Van de Graaff) is used to produce a beam of monoenergetic MeV ions, which is then directed down a beam line and into a target chamber, all of which are under vacuum. There are many different experimental setups in use. Figure 3 shows the main components of both a simple millibeam line and a microbeam line. The millibeam line is typically used for nonresonant NRA and ERD and produces a beam of diameter of order millimeters. The microbeam line shown here has been used for a position scanned microbeam NRA technique and produces a beam of diameter of order micrometers. The resonant NRA technique would use a similar setup to those shown here but with the addition of equipment to scan the energy of the beam. 

For the study of the formation of adducts to macromolecules in animals and in humans, accelerator mass spectrometry (AMS) has been introduced in the field of biomedicine. It is based on the use of a tandem Van de Graaff accelerator and was developed 20 years ago to measure very small quantities of rare isotopes, such as in C dating studies, e.g., for the Shroud of Turin. This technique is now... 

The development of fast ion beam laser spectroscopy techniques (for short FIBLAS) is not so unusual a case of simultaneous but independent technical evolution both in atomic and molecular physics. Although the concepts involved in both cases were quite similar, the apparatus used in the pioneering experiments were widely different, ranging from the table top mass spectrometer for the early molecular physics work to the largest tandem Van de Graaff accelerators for some of the atomic physics experiments. ... 

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