Patrick Janot edited Longitudinal Polarization Experiments.tex  over 10 years ago

Commit id: f37a2b63871eb707aadca7b803cd5d6fd6345391

deletions | additions      

       

Movable spin rotators as designed for HERA~\cite{cite:HERA-beams} would therefore allow a program of longitudinal polarized beams at the Z peak. (The spin rotator design foreseen for LEP requires tilting the experiments and is unpractical for TLEP.) For the same level of polarization in collisions as that observed at LEP, and assuming that a fraction of the bunches can be selectively depolarized, a simultaneous measurement~\cite{Blondel:1987wr} of the beam polarization and of the left-right asymmetry $\ALR$ can be envisioned at TLEP.   It is to be noted that polarization Polarization  wigglers, such as those described for LEP in Ref.~\cite{cite:Blondel-Jowett-LEP606}, will be used at TLEP toefficiently  establish such levels of polarization. Indeed, the natural polarization building time amounted to five hours at LEP, and is predicted to increase like the third power of the ring bending radius. Without polarization wigglers, the natural polarization building time would be nearly 150 hours. The impact of the polarization wigglers on the maximum achievable luminosity will need to be studied. \subsubsection{Polarization at higher energies}