A low-$\beta$ insertion in the PS-SPS transfer line to limit emittance blow-up due to stripping of lead ions for LHC

This paper presents an insertion to reduce the emittance blow-up due to the final stripping (Pb54+ ® Pb82+) by a factor of four, to De*»0.2 mm instead of »0.8 mm measured at the present set up. Reduction to such a small value is motivated by the tight emittance budget for the LHC which calls for a (normalised, r.m.s.) emittance e*=1.5 mm of the lead ion beams at collision energy. Cost estimates of the insertion are given, taking use of existing hardware into account. Fast "switch off" of the insertion is preserved, so that ion and proton beams can be handled on alternate cycles even within the same supercycle. As the commissioning will need a very long MD programme it is proposed to finish the installation during the shut-down 2001-2002.