WP2 - Nanometre-scale beam handling at the ATF

Image: KEK

WP2 covers the programme at the Accelerator Test Facility (ATF) at KEK operating an electron damping ring with ultra-low transverse emittance. ATF2 is a low energy scaled version of a future Linear Collider (ILC, CLIC) final focus beam line where the extracted ATF beam is used to test the sophisticated beam handling techniques planned at the collision point. The operation and R&D programme are managed by an international team involving all the E-JADE partners. Each technical task includes training and transfer of knowledge goals. The main objective of this work package is to demonstrate solutions and methods for final focus systems for future Linear Colliders so as to meet their performance goals. 

WP2 Tasks

Task 2.1: Beam Size Minimisation (CERN, CNRS, KEK & UoT): Reduce effective β* parameter by improving corrections of optical aberrations. Install, commission and operate two new octupole correction magnets. Study alternative optics.

Task 2.2: Wake Field (CERN, CSIC, KEK & RHUL): Calculate and measure wakefields from beam position monitors and collimators. Test novel wake field free steering algorithm.

Task 2.3: Ground Motion (CERN, CNRS & KEK): Measure ground motion (GM) using 14 installed GM sensors synchronised with beam position measurements to assess novel GM based feed-forward algorithm. Test newly developed GM sensor.

Task 2.4: Halo Collimation and Backgrounds (CNRS, CSIC, KEK & RHUL): Calculate and measure beam halo propagation. Develop and test two new retractable collimators for halo reduction. Simulate beam induced backgrounds with GEANT4.

Task 2.5: Beam Instrumentation and control (CNRS, KEK, RHUL, UOXF & UoT): Operate, simulate and optimise performances of existing instrumentation, including laser wire and nanometre resolution beam position and size monitors. Install, commission and operate new radiation hard diamond sensor beam tail monitor. Develop and test new submicron optical transition/diffraction radiation beam emittance diagnostics.

Task 2.6: Beam Position Feedback (KEK & UOXF): Install, commission and operate fast digital feedback for nanometre level beam position stabilization at the collision point. Use beam tracking simulation to model and benchmark feedback performance. 


CERN, CNRS, CSIC, KEK, RHUL, the University of Oxford, and the University of Tokyo participate in WP2. Work package leader is Philip Bambade (CNRS).