| Popis: |
Linear collider damping rings are highly sensitive to magnet alignment. Emittance tuning simulations for current designs of damping rings for TESLA and NLC have given encouraging results, but depend on invasive measurements of dispersion. The frequency with which such measurements must be made is therefore an operational issue, and depends on the time stability of the alignment. In this note, we consider three effects that lead to misalignment and the need to retune the damping ring: (1) diffusive or ATL ground motion, (2) propagation of elastic ground waves leading to correlated motion of the beamline components, (3) uncorrelated motion arising from local noise sources. |
