Abstract :
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For FEL operation of the TTF linac at the final energy of about 1 GeV,
the bunches have to be compressed longitudinally to reach peak currents
of 2.5 kA [1]. With a bunch charge of 1 nC, the compression is carried out
in 2 stages for reaching the final rms bunchlength of 50 microns. Within this
second compressor, where the bunch is very short, coherent synchrotron
radiation (CSR) becomes significant and can induce unacceptable emittance
growth. In this paper, we investigate a 4-bend S-chicane with
a varying compression factor R56. In addition to its simplicity, this
compressor is also dispersion free at all orders. |
