Tesla Polarimeters

We describe a study of high-energy Compton beam polarimeters for the future ee linear collider machine TESLA. A segment of the beam delivery system has been identified, which is aligned with the ee collision axis and which has a suitable configuration for high-quality beam polarization measurements. The laser envisaged for the polarimeter is similar to an existing facility at DESY. It delivers very short pulses in the 10 ps, 10 − 100 μJ regime and operates with a pattern that matches the pulse and bunch structure of TESLA. This will permit very fast and accurate measurements and an expeditious tune-up of the spin manipulators at the low-energy end of the linac. Electron detection in the multi-event regime will be the principle operating mode of the polarimeter. Other possible operating modes include photon detection and single-event detection for calibration purposes. We expect an overall precision of ∆P/P ∼ 0.5% for the measurement of the beam polarization.