A precision mass spectrometer, sensitive enough to detect the ion cyclotron resonance frequency of a single trapped ion, will be used to measure the He/H mass ratio, providing an upper limit on the nest mass of the electron neutrino. It should be possible to determine the mass of a gamma ray and thence the product of Planck's constant and Avagardro's number, also independently determining the fine structure constant in another experiment trapped ion technology will be used to study collision between atoms at energies below one millionth of the temperature of most thermal atomic collision processes, providing understanding of spontaneous decay during the collisions and the use of radiation to switch potential curves during collision
