Study of emittance bumps in the ILC main linac

We present a first look at simulation results of emittance bumps implemented to preserve the emittance growth in the main linac of the proposed International Linear Collider (ILC). It is found that global orbit bumps used as a static tuning option after dispersion free steering can be extremely beneficial in further limiting the emittance growth in the main linac. Two kinds of emittance bumps, dispersion and wakefield, are studied in the present study. The effect of varying the location of these bumps along the main linac and the number of these bumps are studied. The influence of combining these bumps on the emittance growth is also discussed.