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A physicist's fantasy of owning a "tabletop" particle accelerator has been brought one step closer to reality according to research done in France. The accelerator uses two laser pulses to drive an electric field, thus producing monoenergetic electron energies of up to 250 MeV. But unlike previous attempts, the electron beams are stable enough to have practical applications in areas such as radiotherapy and radiography.
(Nature 444 737).