TT2/TT10 Transfer Line Studies for the 14 GeV/C Continuous Transfer

Since several years the values of the emittance of the fixed-target beam measured with SEM-wires in the TT2 line and with SEM-grids in the TT10 line were in disagreement by up to 50 %. The measurement of the beam emittance by means of beam profile monitors (BPMs) relies on the knowledge of the dispersion function at the monitor location. For theses reasons a measurement campaign of the dispersion function and, in general, of the optical parameters in of the TT2/TT10 transfer line was carried out in 1998. The model of the line was verified and the TT2/TT10 line was re-matched according to the measured values of the Twiss parameters and of the dispersion and its derivative. As a result of this work the discrepancy between the emittance values measured in TT2 and TT10 has been brought down to less than 10 % in both planes and the blow-up at injection in the SPS minimised. The transmission through the SPS and hence the intensity delivered to the targets could be increased by about 2 %.