LINAC4 transfer line – optics M. Eshraqi, L. Hein, A. Lombardi (BE-ABP) LINAC4 transfer lines : m (from PIMS out to foil); m new line,then join at BHZ20 the present Linac2 line ( meters from BHZ20 to foil). Active elements : 4+2bendings;16+18 quads,11+11 steerers and 1 RF cavity. 1.Optics 2.Layout 3.Tunability 4.Safety margins L2 PSB L4 ↕ 2.5m

Optics-layout. Uncompensated longitudinal space charge forces, Dispersion and space charge X-Y coupling Bottlenecks : RF cavity; septum, distributor Match the six conditions at the PB (disp=0;dis-1.4;various beta) Contain the emittance increase (30% at max, can be reduced) Accept energy swing of 1.2 MeV At foil: 65mA in pi (rms mm mrad norm) ΔE= keV rms WALLWALL

Optics and tunability X,y rms Ratio aperture/rms above 6 everywhere

Errors and Correctors Static alignment errors can be corrected with steerers Jitter in the bending power supplies should be kept below 10-4 Jitter in linac energy is important for DIS and SEP acceptance bendings10% losses at20% losses at L4T.MBH.0150 / L4T.MBH.0250 ±0.7% of the nominal value±0.8% of the nominal value L4T.MBV.0650/ L4T.MBV.0750 ±6% of the nominal value±6.7% of the nominal value BHZ20±0.5% of the nominal value±0.6% of the nominal value BHZ30±0.9% of the nominal value±1% of the nominal value

AT DIS, beam size-all cases. In 4 rms there is more than 90% of the beam Effect of energy painting is of the order of mm (not included in the plot). D=0 D=1.4 vertical aperture might be the limit for tunability in the case D=0, unless we change yc=5.19 mm

At SMV, all cases, beam size. OK