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First beam tests of the TTF injector

Following tests of the various sub-assemblies at Saclay and Orsay, installation of the entire TESLA Test Facility Injector was completed in Hall 3 at DESY in December 1996. The first phase of operation employs a 250 kV thermionic electron source providing an 800 /spl mu/s train of bunches, each containing 37 pC, and followed by a 216.7 MHz pre-bunching cavity. Subsequent bunching and acceleration is achieved using a standard 1.3 GHz superconducting 9 cell TESLA cavity operated in pulsed mode (10 Hz). Prior to injection in the main linac, the beam parameters are verified using a spectrometer consisting of a dipole magnet and SEM profile monitor. Once the beam is adjusted it is transported to the linac using an optical matching system employing two triplets. We present results of the first beam tests of the completed injector which took place early in 1997.