2011/10/14 by Nicolas Delerue, Delerue, Nicolas, J. Bonis +67
Engineering · Physics and Astronomy · #Accelerator Physics (physics.acc-ph) #Atomic and Subatomic Physics Research #FOS: Physical sciences #Particle Accelerators and Free-Electron Lasers #Particle Detector Development and Performance #physics.acc-ph
paper · pdf · doi:10.48550/arxiv.1110.3243
arxiv created 2011/10/14 · openalex publication_date 2011/10/14 · arxiv updated 2011/10/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The next generation of e+/e- colliders will require a very intense flux of gamma rays to allow high current polarized positrons to be produced. This can be achieved by converting polarized high energy photons in polarized pairs into a target. In that context, an optical system consisting of a laser and a four-mirror passive Fabry-Perot cavity has recently been installed at the Accelerator Test Facility (ATF) at KEK to produce a high flux of polarized gamma rays by inverse Compton scattering. In this contribution, we describe the experimental system and present preliminary results. An ultra-stable four-mirror non planar geometry has been implemented to ensure the polarization of the gamma rays produced. A fiber amplifier is used to inject about 10W in the high finesse cavity with a gain of 1000. A digital feedback system is used to keep the cavity at the length required for the optimal power enhancement. Preliminary measurements show that a flux of about 4×106 γ/s with an average energy of about 24 MeV was generated. Several upgrades currently in progress are also described.