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This low level of beamstrahlung provides several advantages, some examples of which are given below.  \begin{itemize}  \item Beamstrahlung is a macroscopic effect that cannot be predicted from first principles, and the resulting beam-energy spectrum needs to be measured in situ, withcorrespondingly  significant statistical and systematic uncertainties. The measurement of observables relying on a precise beam-energy knowledge (e.g., Z or W masses, Z width, top quark mass, etc.) therefore greatly profit of the relative absence of beamstrahlung. Similarly, cross sections with a rapid variation as a function of the centre-of-mass energy (e.g., at the Z pole, or at the WW and $\ttbar$ thresholds, as shown for example in Fig.~\ref{fig:ttbar} of Section~\ref{sec:EWSB}) are {\it (i)} maximal; and {\it (ii)} calculable with very good accuracy, leading to small statistical and systematic uncertainties. \item The forward region of a TLEP detector is free of beamstrahlung photons, which in turn eases both the design of a luminometer and the integrated luminosity measurement. Likewise, the beam-related backgrounds (disrupted beams, photons, $\epem$ pairs) originating from beamstrahlung are small, and so are the parasitic $\gamma\gamma$ collisions. Pile-up interactions are therefore negligible.  \item Final states with photons (e.g., ${\rm H} \to \gamma\gamma$, ${\rm H \to Z}\gamma$, or $\epem \to {\rm Z}\gamma \to \nnbar\gamma$) can be selected with optimal purity.   \item The quasi-absence of beamstrahlung photons along the beam axis (in both directions) enables an optimal use of energy and momentum constraints in kinematic fits.