decay will have a mass and charge different from those of the original nucleus.
Nuclei consist of positively charged protons and electrically neutral neutrons held together by the so-called strong or nuclear force.
This force is much stronger than the familiar electrostatic force that binds the electrons to the nucleus, but its range is limited to distances on the order of a few x10.
This is a large nuclear particle accelerator based on the principle of a Tandem van de Graaff Accelerator operating at 0.2 to many million volts with two stages operating in tandem to accelerate the particles.
At the connecting point between the two stages, the ions change charge from negative to positive by passing through a thin layer of matter ("stripping", either gas or a thin carbon foil).
Additionally, the impact strips off several of the ion's electrons, converting it into a positively charged ion.
In the second half of the accelerator, the now positively charged ion is accelerated away from the highly positive centre of the electrostatic accelerator which previously attracted the negative ion.Individual ions are finally detected by single-ion counting (with silicon surface-barrier detectors, ionization chambers, and/or time-of-flight telescopes). Alvarez and Robert Cornog of the United States first used an accelerator as a mass spectrometer in 1939 when they employed a cyclotron to demonstrate that He was stable; from this observation they immediately and correctly concluded that the other mass-3 isotope tritium was radioactive. Muller at the Lawrence Berkeley Laboratory recognised that modern accelerators could accelerate radioactive particles to an energy where the background interferences could be separated using particle identification techniques. His paper was the direct inspiration for other groups using cyclotrons (G. Yiou, in France) and tandem linear accelerators (D. Thanks to the high energy of the ions, these detectors can provide additional identification of background isobars by nuclear-charge determination. There are other ways in which AMS is achieved; however, they all work based on improving mass selectivity and specificity by creating high kinetic energies before molecule destruction by stripping, followed by single-ion counting. All of the elements heavier than uranium are man made.Among the elements are approximately 270 stable isotopes, and more than 2000 unstable isotopes.Cl), which is not suppressed at all by the setup described so far. Soon afterwards the Berkeley and French teams reported the successful detection of Be, an isotope widely used in geology.