A. Lyapin

Present status and first results of the final focus beam line at the KEK Accelerator Test Facility

ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U. S. scientists. The present status and first results are described.

Results from a prototype chicane-based energy spectrometer for a Linear Collider

The International Linear Collider (ILC) and other proposed high energy e{sup +}e{sup -} machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 10{sup -4}. This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006-2007 in SLACs End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5 {center_dot} 10{sup -4} was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance.