Self-amplified spontaneous emission for a single pass free-electron laser

Physical Review Special Topics - Accelerators and Beams (Impact Factor: 1.66). 06/2011; 14(6):060712. DOI: 10.1103/PhysRevSTAB.14.060712


SPARC (acronym of ''Sorgente Pulsata ed Amplificata di Radiazione Coerente'', i.e. Pulsed and Amplified Source of Coherent Radiation) is a single pass free-electron laser designed to obtain high gain amplification at a radiation wavelength of 500 nm. Self-amplified spontaneous emission has been observed driving the amplifier with the high-brightness beam of the SPARC linac. We report measure-ments of energy, spectra, and exponential gain. Experimental results are compared with simulations from several numerical codes.

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